Battery build & Controller Upgrade

[ElectricGSXR]

I'm new here so I'd like to first say hello. I'll apologize in advance if any of my questions or statements seem stupid as I am new to all of this and it is a lot to process.
I am in a bit of a pickle. I have to get a new battery for my electric motorcycle. I don't like the looks of the ones (that I can find for sale) on amazon.ca and I don't know where to get another one. I know I could most likely go to the place where they sell the Emmo bikes and try to get a new Lit-Ion battery there but it would cost a lot to get another like the one I had which was 72v 80Ah Lith-Ion with 100amp BMS - I took a picture of that information. The bike that I have has a 3000w rear hub motor, I am uncertain of the peak watt rating of my particular motor but when checking a similar QS hub Motor online today it says 3000w / 8000w peak. I have no idea what controller I have which is something I should probably check soon.
I have been looking at a lot of information on the internet and videos on YouTube and I think that I could likely take on the task of building one for myself. The cells I would use are a 3.2v 90Ah rated for C3 so that's 270amps? The C rating is confusing me. Link for battery below.

https://www.aliexpress.com/i/4000805306784.html?spm=a2g0o.productlist.bottomlink.1.7e79qWXvqWXvWq

I'll connect them in 24S to get my 72v which is the option on the Daly BMS I am thinking about getting. I am not set on Daly but have read mostly good things. I have read however that you can't really trust the ratings that they say for any of the BMS' you buy from China and that's exactly where I plan on getting my stuff from, but the bike came from China in the first place so the BMS originally in the battery was from China and it worked fine. Had it for 3 years and I ride as much as I can. I think it just ran its life. My old battery pack had a 100amp BMS but I'm not sure of the peak and I cant find the peak ratings on the Daly BMS shown below it only shows the amps. I am not really sure if I need to get a bigger BMS or not if I make a new battery with those cells.
Link for the Daly BMS I am considering below, its the 72v 24S LiFePO4 version. Not sure on the amp rating I need though. I cant find the peak amp ratings there either but maybe I'm just not seeing it.

https://www.aliexpress.com/item/1005002897035148.html?pdp_npi=4%40dis%21CAD%21C%24%2073.23%21C%24%2036.73%21%21%2152.84%2126.50%21%402103244817113034905313265e6a7e%2112000035364534505%21sh%21CA%210%21&spm=a2g0o.store_pc_allItems_or_groupList.new_all_items_2007550510536.1005002897035148#nav-review

I did calculations for my motor @ 3000w + 15% as was advised in something I read, so 3450w divided by 72v is about 48amps
I also did the 8000w peak divided by 72 which is around 111amps
Then I did calculations for when the battery pack's voltage is full which I got as 88v at 100% full and a lower voltage at 40% which was around 47v.. If that makes sense.
So I got 3450w divided by 88v (100% full) = 40amps
and 3450w divided by 74v (at 40%) = 74amps
I figured I would check what I thought would be the worst case scenario which was the motor peaking at 8000w divided by 47v = 170amps peak

With that all gathered & assuming its correct... I'm guessing my old BMS was 100amp with close to 200peak? Would something like that work with the battery pack I plan on making?
Again, the cells are: 3.2v 90Ah 3C Max Discharge in 24S so the pack is: 72v 90Ah 3C Max Discharge.

For my controller I mean I honestly don't know much about them. I have to check which one I have and everything still. I don't have the software or anything (if there was anything) since I bought the bike from a friend and they aren't living in the same city anymore. I really want to get a new controller as well so I can have the option to manage and monitor different things in the future.

This has gotten my brain activated for sure. I'm confused but slowly gathering little bits. Any help appreciated.

 

[amberwolf]

like the one I had which was 72v 80Ah Lith-Ion with 100amp BMS

I have no idea what controller I have which is something I should probably check soon.

Yes, you will require the controller information, especially its' battery (not phase/motor) current limit, before you can build or buy a battery that can supply it.

You can *guess* that the battery must supply no more than 100A peak for a few seconds, but it's much safer to find out.

I have been looking at a lot of information on the internet and videos on YouTube and I think that I could likely take on the task of building one for myself. The cells I would use are a 3.2v 90Ah rated for C3 so that's 270amps? The C rating is confusing me. Link for battery below.

https://www.aliexpress.com/i/4000805306784.html?spm=a2g0o.productlist.bottomlink.1.7e79qWXvqWXvWq

Take every rating you see on any of these things (battery, BMS, motor, controller, etc) with a shaker full of salt.

I can't say anything specific about this cell vendor, but a few things are not uncommon:

Inflating the ratings by however much it takes to sell as much product as they need to. Selling less-than-perfect (or worse, or used, recycled, etc) cells as if they were perfect and new. Some others I was going to type but got distracted by JellyBean needing attention and forgot for the moment. :/

Also, I don't know of any of them that match the cells to each other when selling more than one, so they don't all behave the same in charge or discharge, and thus the usable capacity and performance of the pack gets worse and worse with time even though the cells themselves aren't any different***. Commonly called out of balance, it means the voltages are different so the state of charge is different, and the lowest capacity cells get higher and higher in voltage as they fill up before the better ones, so charging stops with the others still nowhere near full, etc.

A BMS with balancing function will eventually correct the voltage difference given enough time left on the charger (hours, days, or weeks, depending on the cell differences), but it odens't do anything to fix the actual cell differences--that requires replacing all the cells with identical matched ones.

Most batteries not made for or by large OEMs (primarily automotive) that must deal with long warranty periods won't be made with matched cells, as it may be significant extra effort for them to do this, and leave them with cells they can't use at all that don't match enough others to build a pack from.

Same-batch cells *should* be identical, but it's not always true even of good quality manufacturers, and it's likely that lesser manufacturers don't have consistent enough processes to make identical cells even in the same batch, so they would have to be manually matched for a pack build to be the best it can be for the longest time.

***the cells also do change over time, but if they're matched and good quality they'd all change at the same rate, so still remain balanced even as capabilities and capacities decline with age).




Ok....all that said:

The cells you link to should, from the specs on that page (pasted below), be capable of a *maximum* of 270A discharge. But it doesn't say how long they can handle that, so you would have to either determine that experimentally by seeing how much they heat up (so they don't exceed the 55C rating below) when built into the complete pack with compression hardware**** and protective casing, etc., or see if you can find the actual manufacturer website with data sheets that have this information. (which you'll probably have to use the google transate app or other photo-translation website to read).

Most likely it will be much less than that continuous. Safer to assume less than half the max value. Again, would require experimental testing to find out. A continous rating should not heat the cells at all. If they are generating measurable amounts of heat, their internal resistance is so high that they are wasting power as heat inside themselves instead of delivering it to your wheel to move you.




This type of cell (prismatic), or pouch cells or other non-cylindrical cells, will need compression on the large faces to keep them flat during usage. Without that, it's likely that outgassing in the cells will degrade them; they'll show this by swelling up, and how quickly this degrades things depends on the mechanical layer structure within the cell and what happens to it as the gas distorts and delaminates the layers.

There's a number of threads discussing cell compression, with pictures of assorted methods, etc., but essentially you should plan your pack build to have as many cells as possible in each module, all with their largest faces against each other, and allow for probably at least one cell's thickness of compression hardware on the ends of each module.

You'd want something to immobilize all cells relative to each other anyway, so no strain is placed on the terminals from the busbars; the compression hardware will do this for everything in the same stack.

I'll connect them in 24S to get my 72v which is the option on the Daly BMS I am thinking about getting. I am not set on Daly but have read mostly good things.

If you get them right from the Daly manufacturer, maybe (which that ali* page probably is)...but there are many counterfeit items out there and it's possible that the various Daly failures (including Methods' threads about them) are from that, rather than the real ones having poor design and manufacturing (as he found with the ones he diagnosed and tested).

I don't know that JBD or JK (JKL?) or ANT are significantly better, but I haven't seen the kinds or amounts of reports of failures of those as I have Daly here on ES.

None of the available BMSes have sufficient documentation from the manufacturer to really know how they operate or what their design is, and many don't even have enough to fully set them up without a fair bit of guesswork and/or experimentation. :/

(I don't use a BMS as I am using (now-ancient) cells designed for much more capability than my system requires, so I'm never pushing them anywhere near their limits, and they are as perfectly matched as one could ask for so they never become imbalanced, etc).

My old battery pack had a 100amp BMS but I'm not sure of the peak and I cant find the peak ratings on the Daly BMS shown below it only shows the amps. I am not really sure if I need to get a bigger BMS or not if I make a new battery with those cells.

Your BMS must be sized for two things:

It's most important job is to protect the cells. So any and all of it's limits must be *less* than the cells' real capabilities as used in your application, to prevent damage to the cells. It can be more *capable* than that, but it must be limited to less so it shuts off output to protect the cells in case of overcurrent.

Next, it must be able to supply whatever the controller asks for without shutting down the power to the system because of overcurrent limits. That means that whatever the controller current limits are, both peak and continuous, must be lower than whatever the BMS limits are (or rather the BMS must be better than the controller).

So, overall, what your battery has to be depends on what your controller will ask of it.


If something doesn't show a peak vs continuous rating, and doesn't say what the rating it does give you is, it's probably safer to assume that all ratings are peak, and cut them in half for any continuous usages you need them for. If it turns out that the rating is actually continuous, at least it'll never be stressed.

I did calculations for my motor @ 3000w + 15% as was advised in something I read, so 3450w divided by 72v is about 48amps
I also did the 8000w peak divided by 72 which is around 111amps
Then I did calculations for when the battery pack's voltage is full which I got as 88v at 100% full and a lower voltage at 40% which was around 47v.. If that makes sense.

If you ran a 24s LiFePO4 battery down to 47v, that would be 47v / 24s = 1.96v which is almsot certainly below the allowable minimum empty voltage (LVC) for the cells. It's certainly far below 40% charge. You'd need to find the manufacturer data sheet for these specific cells to know what their actual allowable voltage range is, and hopefully also an SoC chart to say what voltage they'd be at for various states of charge at various discharge and charge currents.

(see the testing data for various tiny cells over at lygte-info.dk for examples)

So I got 3450w divided by 88v (100% full) = 40amps
and 3450w divided by 74v (at 40%) = 74amps
I figured I would check what I thought would be the worst case scenario which was the motor peaking at 8000w divided by 47v = 170amps peak

It doesn't really matter what your motor wattage is, for what the battery needs to supply.

It only matters what your *controller* is going to draw from the battery, worst case and for how long, and continuous.

 

[Dui ni shuo de dui]

building one for myself. The cells I would use are a 3.2v 90Ah rated for C3 so that's 270amps?

Yes, that's how it works.
Capacity x C rating = max discharge rate.

So I got 3450w divided by 88v (100% full) = 40amps
and 3450w divided by 74v (at 40%) = 74amps

No, it doesn't work like this, the battery voltage does not decrease linearly during discharge.
You need to check the cell data, there should be a discharge curve graph, that will tell you the actual voltages for a given state of charge. For LiFEPO4 the minimum voltage per cell should be around 2.9V, so that's 2.9V x 24S = 69.6V or so.

I suggest you to buy a 300A BMS, either the ANT or the Daly.
Personnally I prefer the ANT, I tried the Daly and didn't like the balancing system, but most people prefer the Daly because if comes with a nice looking enclosure.

These BMS are programmable, so you can set the maximum current to whatever you want (in this example, it would be 270A or a little bit less, typically you set it around the maximum theroretical disharge rate of your battery, minus a safety margin if you want the battery to get less stressed and last longer, but that also depends on your controller). The current value needs to be bigger than the one your controller needs, otherwise the BMS will cut power when you accelerate. So for example if your controller needs 250 battery amps, then you need your BMS to be set to 250 A at the very least.

Getting a BMS capable of more amps than you need is always a good idea if you can afford the extra cost. It'll be more reliable, more efficient and also you'll be able to reuse it if you plan on building a bigger/more powerful battery in the future.
The first thing you need to do is to look at what controller you're having, checking only the motor won't give you any real clue as to what battery you need.

Also, it is a good opportunity to think about potential upgrades, if you want to get more power on your setup now is the time, as battery is almost always the limiting factor in most builds. Always get the most powerful battery you can afford. It would suck to make a bigger battery and then a few months later you find that you'd like to upgrade your controller or motor but you can't because the battery won't handle it.

So, to sum up:
1- check what controller you have and report here
2- set your final goals for the build: more power? more range?
3- Define your resources : how much $$ are you ready to spend? what are your DIY skills? Do you have the necessary tools?
4- We'll try and help guiding you towards what hardware you'll need to reach these goals

Also, a few pictures are always very much appreciated, as they usually worth a thousand words

Good luck with your project.

 

[Chalo]

I suggest you use a cell balancer rather than a BMS, and set up the rest of your system so that the charger can't overcharge your pack and your speed controller can't overdischarge it. Easier, cheaper, more fault tolerant, less likely to leave you stranded.

 

[Dui ni shuo de dui]

I suggest you use a cell balancer rather than a BMS, and set up the rest of your system so that the charger can't overcharge your pack and your speed controller can't overdischarge it. Easier, cheaper, more fault tolerant, less likely to leave you stranded.

If I may, it's certainly not easier, cheaper nor more reliable to add a separate board than just use one that features it in the first place.
I'm yet to see a balancing board go wrong on an ant BMS, not saying it isn't possible but I havent heard of this failure mode in the many years I've been using them, so I wouldn't say it's something that happens a lot.

The charger max voltage being slightly lower than the maximum voltage of the pack is good advice though, if that's what you were saying.

 

[ElectricGSXR]

Thanks for all of the great info so far!

So, I am limited with space and also budget which I have set at around $2500-$3000 CAD.
The box I had put together for the previous battery fits the space well on the bike, and also fits the 24S battery configuration with the cells that I mentioned previously. The dimensions for the box are 16in x 9.5in x 12in (LxWxH). Battery pack, assuming the dimensions they give for each cell are correct on aliexpress would have it at 15.6in x 7.7in x 11.2in (LxWxH)
I'll probably have to build a new box for the new battery though. Which won't be much money in sheet metal in relation to the rest of the cost of the items. However the plastic fairings/cowlings will stop the battery box from being too much wider I do know that for certain, and I can't live without them they make the bike look amazing.
As for the length of the box (which is what matters most for my battery pack/individual battery cell configuration) I could get more out of the space I think, not enough to increase cell size but enough for extra padding for sure. I will post more pictures of my bike and also a drawing I made of the battery pack and BMS. Battery pack is 8 cells tall and 3 cells wide(24). I have it configured with the BMS sitting on top but I think I have to look further into compression and what Amberwolf was talking about.
I think I can get more out of the space all around tbh I just have to get back out there strip down the bike and start taking measurements letting my brain start processing/thinking of ways to do it. I had built the box that is on the bike now by drilling and tapping out holes on aluminum angle and fastening on sheet metal panels. I now have a small welder so there's more options than I previously had.

I don't do a lot of DIY stuff. I'm off work right now but I am a tradesman in the HVAC field so I have a decent understanding of electricity/understanding of how to use a volt/amp meter.. and hands on capability/willingness to try. I have most tools I think are needed but as of right now the one tool I will need to purchase will be a wire crimper. I will also need to purchase the stuff to build the pack like some copper to make my own bars, the tape and shrink wrap ect. but that's nothing I'm worried about.

I'm not really looking to upgrade the battery or anything, I tried to keep the specs similar to the old battery I had.
I really just want to get riding again
In the future I plan on converting a Honda CB550 or something similar to electric but that will be much later down the road. The sport bike look is really nice I love it.. but I will be able to get much more out of a cafe-racer style bike in terms of space for battery, especially if I go with a hub motor. Mid drive would be really cool though and is highly reviewed but I would lose quite a bit of battery space. Hub motors aren't that bad honestly and I think that either 5000w or 8000w would be amazing. My little 3000w motor gets me 70-80km top speed and honestly I don't need much more than that. I know I am probably overworking it though so I would like to get either 5k or 8k watt in the future.

Here is a picture of the information that's on the controller. I'll post more pictures as well. Also below is a link to what I think is the exact same controller on AliExpress. I don't think I will get a new controller as it looks like I can just buy the Bluetooth dongle separately. I will check to see that it has the bluetooth plug in first but if I can get access to the app with the controller I have that's good enough for me and really all I want.

https://www.aliexpress.com/item/33041790484.html?pdp_npi=4%40dis%21CAD%21C%24%20253.81%21C%24%20244.77%21%21%21182.45%21175.95%21%402101fb1517113882266481402ec69c%2112000026390201862%21sh%21CA%210%21&spm=a2g0o.store_pc_allItems_or_groupList.new_all_items_2007523631241.33041790484

 

[ElectricGSXR]

There's pictures of the new battery pack design I drew up (I hope it makes sense), my bike itself and the old battery info.

 

[amberwolf]

As for the length of the box (which is what matters most for my battery pack/individual battery cell configuration) I could get more out of the space I think, not enough to increase cell size but enough for extra padding

Remember really what you need is cell stack compression, and something that completely fixes the battery and interconnects in place relative to each other (the one would ideally also do the other). As long as both of those are true you don't really need any padding to absorb vibration, etc. If you need impact protection then a sturdy frame around the battery that can't be deformed by any impacts that would leave the bike in working condition

That kind of frame is likely to be difficult to implement without rebuilding the bike frame itself to do this job, so your best bet is to just secure the battery compression/etc housing to the frame as well as possible. If you suspect vibration will be an issue, you can use anti-vibration "grommets" at those fasteners, similar to the type of mounting used on many AC compressors, vaguely like these:

anti-vibration "grommets" - Google Search

but keeping in mind the max loading that the mounting location, bolt and grommet will have to take. (if compressed too far they tend to split open and let the mounted device rattle around instead, making the problems much worse than if they were just bolted right down).

I have most tools I think are needed but as of right now the one tool I will need to purchase will be a wire crimper.

There's a few threads about them; Liveforphysics has a few good posts with specifics.

I'd rather have hydraulic ones, but the ones I could actually afford are these:
https://www.amazon.com/gp/product/B00Y7M7SG6
that come with mulitple dies and are at least ratcheting.The strippers that come with them are alright, but none of the kit pieces are very well made (not junk, but nothing like the Amphenol and other company-brand stuff I have had from last century).

Hub motors aren't that bad honestly and I think that either 5000w or 8000w would be amazing. My little 3000w motor gets me 70-80km top speed and honestly I don't need much more than that. I know I am probably overworking it though so I would like to get either 5k or 8k watt in the future.

Remember that it's not the motor that provides the power; it's the battery, then the controller. The motor just translates that power into motion, and has to handle the waste heat from the conversion.

Here is a picture of the information that's on the controller.

It says 80A, so that means it's probalby 80A continuous given the speeds you're using it at, and the power needed for that. Might be 80A peak; no way to know uniless you have an independent wattmeter / ammeter on the system to measure this.

So whatever battery/etc you get just needs to handle that continuous load, and potentially (but not likely) twice that peak for a few seconds at worst-case loads / startup from a stop, etc).

 

[ElectricGSXR]

I like those cells because I don't have to do any spot welding and they looked very easy to work with. I have of course been looking around for other options and I came across some LiFePO4 cylindrical ones. Maybe I should look at something like that instead since they are less bulky and will need less compression?

Something like these:

https://www.aliexpress.com/item/1005004218323188.html?pdp_npi=4%40dis%21CAD%21C%24%20165.57%21C%24%2056.30%21%21%21119.02%2140.47%21%402103244817114139206594974e6a7a%2112000028416599309%21sh%21CA%210%21&spm=a2g0o.store_pc_allItems_or_groupList.new_all_items_2007472982090.1005004218323188

I still get the benefit of having the studs like on the prismatic cells but they look like they will be much more difficult to configure unless I can find the cell holders that will fit them like the 18650 or 21700 cell holders. If I can find the correct cell holders I am starting to think something like that might just be the way.

If I were to do 8P 24S I would have 72v 160Ah tucked in a much smaller space. I could probably add another 16 cells to that with space for the BMS if I could afford it all.
I have a question about wiring them in parallel. I know it increases the capacity but would I also be increasing the constant current and the max discharge current capabilities of the overall pack? How do I check the math for that I would love to know. I feel stupid lol I haven't dealt with battery packs and this kind of electrical before. I mostly do HVAC installations I really wish I knew more on the electrical side of things and troubleshooting now.

 

[amberwolf]

I like those cells because I don't have to do any spot welding and they looked very easy to work with.

Yes, they are a very simple option. You could use them without compression, but I would recommend compression if it's possible to do so. Doesn't take a lot to do it, if the end plates are stiff enough to not bend or deform you can use bolts at the corners or straps around the stack, etc. See Dogdipstick's posts about the packs he builds for images and data on that method.

I have of course been looking around for other options and I came across some LiFePO4 cylindrical ones. Maybe I should look at something like that instead since they are less bulky and will need less compression?

Cylindrically cells provide their own compression by design. It would be difficult to create a containment for them that could provide further compression without greatly increasing your pack size (since you would need to be able to create and adjust that compression during installation, so you can't just drop them into tubes).

They are also *more* bulky, as there is always wasted space between the cells, and more complicated to create a pack from because they require multiple parallel cells to be interconnected, which also creates more chances for interconnect failures over the life of the pack.

To make a pack from these equivalant to your existing pack you'd need at least 5 of these in parallel in each group, x 24 of those groups of 5. You'd need at least six of the cylindricals in parallel in each group to make a pack equivalent to the prismatic ones in 1P.

They don't state the C-rate or current capability of the cylindricals in their specification images (pasted below), but their IR is six times that of the prismatics, while their capacity is 2/9ths, so they don't perform proportionally as well as the prismatics.
EDIT: there are futher specs (pasted below) in text that state 10A continuous in one place, and 60A continuous in another, and 100A max. I wouldn't trust anything they say, but if i had to go with a number, I'd say that it's safer to assume the 10A is continuous and 60A is peak and 100A is not real.

In the latter event then it would take at least 8, and probably more like 10+ of them in parallel to do what your original battery did.

The weight is listed as 0.37kg for the cylindricals, 5x that is 1.85kg, so less than one prismatic at 2.05kg, but if you use six to make them equivalent IR that goes up to 2.22kg and is more than one prismatic.

So, if you only need 5p, then the whole block of cells is only going to be about 45kg (not including any interconnects, housing, wiring, BMS, etc; call that another 5kg just to round it up to 50), so call it 100-110lbs. What does your present pack weigh?

Volume-wise, you can put cylindricals in alternating rows that either stack like honeycomb or in a grid; it'll be a little less in one direction than another each way, but total volume ends up the same. So you can calculate your pack size from the dimensions they give for the cells to see if it would fit, and what it is compared to the prismatics for enough capability to run your system as needed.




All of the other caveats about cells from sites like this also apply to these (and every other type of part).




EDIT: Looks like they have english specs in the ad buried further down, but like most of these things they make them sound worse, not better. For instance, teh capacity says "minimum 19Ah" which means you could buy 20Ah cells that can't actually supply more than 19Ah, and that's ok with them because they told you in advance you're buying parts that don't meet the spec, so you can't complain about it. If this brand's "Grade A+" is spec'd like this, I personally wouldn't want to buy anything they make. But I'm picky.

They also say that the IR is *less than 0.3milliohm" in these specs, but the image says 3.00milliohm, and I suspect the image is more likely to be correct.

In the image they say 2.0v cutoff, but in the text they say 2.5v; the higher voltage is more likely correct. But inconsistencies in specs usually mean they dont' know what they are talking about, or are copy/pasting info from multiple sources and/or for different parts, so I wouldn't actualy trust *any* of the info provided for *any* of the items they sell (or make).

Battery Sepcification: Brand:LiitoKala Battery type: lithium iron phosphate Product Name: LiFePo4 Battery Cell Model Number:3.2V 20Ah 64Wh/VAh Nominal Voltage: 3.2V Rated Capacity: 20Ah Minimum Capacity: 19Ah Grade: Grade A+ Quality: Brand 100% New Housing Material: Aluminum Internal Resistance: Less Than 0.3mΩ Suggested Constant Current: 10A (0.5C) Discharge Cut-Off Voltage: 2.5V Maximum Charging Voltage: 3.65V Maximum continuous discharge current: 100A (5C) Constant current: 60A (3C) Charging method: CC / CV Charging voltage: 3.65V Cycle life: ≥4000 times (80% DOD) Charging temperature: 0~60°C Discharge temperature: -20~60°C Size:40.5*163(±20)mm Battery weight:0.37± 0.1 kg Screws Type: M6

 

[ElectricGSXR]

The old battery I had weighed about 60-70 pounds id say maybe more maybe less. It was pretty heavy. I don't have it anymore.

I did notice a bunch of wrong information in that ad too but I just grabbed the link as a reference more than anything. I would like to find something like them though. That style looks like the best option for me with the limited space. I'm going to look more into the cylindrical ones with the studs.

I think I found the same ones on Alibaba.. I don't really trust what they say though. Looks more or less the same.

40135 C40 Lifepo4 20000mah Cylindrical Cell Lfp Lithium Ion Battery 3.2v 20ah Cylinder 40135 Lifepo4 Battery - Buy 40135 Lifepo4 40135 3.2v 20ah Lifepo4 Battery Cell Product on Alibaba.com

40135 C40 Lifepo4 20000mah Cylindrical Cell Lfp Lithium Ion Battery 3.2v 20ah Cylinder 40135 Lifepo4 Battery - Buy 40135 Lifepo4 40135 3.2v 20ah Lifepo4 Battery Cell Product on Alibaba.com

www.alibaba.com

These don't look like they have the stud though.. Same specs

EVE C40 40135 20Ah Cylindrical LiFePO4 Cell

EVE C40 40135 3.2V 20Ah Cylindrical LiFePO4 battery Cell

www.evlithium.com

and these....

Cylindrical cells LiFePO4 3.2V 100Ah

lifepo4 cylindrical battery cell 3.2V 100Ah lithium lifepo4 battery for energy storage, solar system.

www.evlithium.com

 

[amberwolf]

Generally, I advise that if you don't trust info you see, or there is mismatching info (or missing important info), or something looks fishy, confusing, or too good to be true, I'd just plain avoid the entire seller or manufacturer. Saves a lot of grief and lost money and wasted time.

There are also quite a few threads and posts here about "trustworthy" or "reliable" or whatever batteries, vendors, etc. Even though some of htem are pretty old, it's likely that any "avoid" advice in them is still good, even if recommendations from them might have changed.

Sometimes wrong info is just a mistake...but it's so hard ot communicate effectively with most of these sellers that it is very difficult to be certain you're really clarifying anything, and that they aren't just saying whatever you want to hear so you'll buy from them.

 

[Dui ni shuo de dui]

I'm not really looking to upgrade the battery or anything, I tried to keep the specs similar to the old battery I had.
I really just want to get riding again

Ok, but keep in mind that your battery died, so it's probably a good idea to beef it up a bit if you don't want history to repeat itself.

My little 3000w motor gets me 70-80km top speed and honestly I don't need much more than that. I know I am probably overworking it though so I would like to get either 5k or 8k watt in the future.

If you do, then you are likely to need a bigger battery, hence my remarks earlier: the battery must absolutely be the most powerful component of any build.
To be fair, you are very far from maxxing out your motor. Right now your controller power is 72V x 80A = 5760W. What you need to understand is that the rating on the QS motors don't really mean anything, these motors can take way more power than what's written on the covers. See, on your bike for example, the motor takes almost 6KW from the controller.

I have a bike that's very similar to yours and I was still using a 3KW motor until two months ago. But, thanks to a much more powerful controller , I was able to reach around than 400A from the battery so that's 72V x 400A = 28KW or so. The 3KW motor sure heated up fairly quickly, but it's still in good shape.
I had it running reliably at 16-20KW for around 6 years or so. So my point is, you don't need to change your motor unless you go for some really super powerful controller, or if you live somewhere where there are mountains to climb.
Maybe you can throw a quick look at my ninja build thread, since both our bikes are very much alike, it might give you some inspiration

Here is a picture of the information that's on the controller. I'll post more pictures as well. Also below is a link to what I think is the exact same controller on AliExpress. I don't think I will get a new controller as it looks like I can just buy the Bluetooth dongle separately. I will check to see that it has the bluetooth plug in first but if I can get access to the app with the controller I have that's good enough for me and really all I want.

Yeah this controller is the infamous Yuyangking. It is quite crappy, that would be the first thing I'd change if I were you. At only 80A the acceleration is lame, you really should consider upgrading this to something more adapted. I'd say 150A is the very bare minimum for a bike of this size and weight. Even 150A is really on the low power side of the spectrum.

I like those cells because I don't have to do any spot welding and they looked very easy to work with.

If I were you, I'd consider purchasing a pack made of automotive grade cells. On my builds I'm using the A123 pouch cells, they came already assembled and compressed since they were taken out of a vehicle. Maybe you can check where you live if you are able to find them, as they are extremely good (high discharge rate and litterally bullet proof, mine were made in 2012 and still work perfectly to this day). Other people used nissan leaf modules and seemed happy with them. I guess there are lots of other choices now with so many new EVs on the market, it's been a while since I haven't looked into available battery tech.

Automotive grade cells are made to widstand all the vibrations and constraints of daily riding, their quality control is miles better than anything you'd use for stationary applications. Car manufacturers can't afford bad press on batteries, or worse, recalls. That would mean instant bankrupcy.
So if I were you I'd look for second hand cells from dismantled cars already assembled into packs. Then your only task will be to assemble the BMS, add power leads and build some kind of enclosure. It's already plenty of work. No idea how easy it is to find where you live tho.

 

[ElectricGSXR]

Thank you for the advice (and inspiration) I had a look at your Ninja and it's awesome.

I found this place which sells something similar to what you had put in your bike:

A123 26s3p(72V) pouch battery modules - BRAND NEW!

These Brand New A123 batteries were part of a conversion that fell through. We have several hundred of these modules that are now available for dirt cheap!

www.greentecauto.com

I'm not sure of the cost to get it to Toronto Canada but it looks great. I would have to open it up and wire in a BMS they say though or purchase the Master Control Unit.

 

[Dui ni shuo de dui]

Thank you for the advice (and inspiration) I had a look at your Ninja and it's awesome.

I found this place which sells something similar to what you had put in your bike:

A123 26s3p(72V) pouch battery modules - BRAND NEW!

These Brand New A123 batteries were part of a conversion that fell through. We have several hundred of these modules that are now available for dirt cheap!

www.greentecauto.com

Well that's pretty much perfect, if you can find a way to fit them in your bike I can't think of anything better. These batteries are absolutely awesome.

 

[ElectricGSXR]

If I buy that battery which BMS would you recommend I get for it and if I were to upgrade controllers would there be one you recommend? I see you like the bms you have and have also been through many controllers in testing. I guess the only thing will be to upgrade the motor in the future so should I size the controller and everything now for the 6000w motor like you have on your Ninja? I will just go with what you have if I can it looks fast and well done. Amazing.

I cant find any BMS' with 600amp /1000amp peak 26S. I think that will be hard.

26.5 inches long will be hard to fit as well I think.

For tomorrow.

 

[Dui ni shuo de dui]

If I buy that battery which BMS would you recommend I get for it

The one I use is the ANT BMS 300A.
The 300A rating is actually a continuous rating, it can take a little bit under 600A peak.
That's more than you'd need for any reasonable build, I can't even reach that on my build so far.

and if I were to upgrade controllers would there be one you recommend?

The nanjing Fardrivers are good, but recently they made some shit business decisions with passwords for their app, wechat mini programs and shit like that. People have been complaining a lot, they are difficult to set up, the documentation sucks and the support isn't good at all.
But once they work, they work really well.

I also tried the Votol controllers, which are perhaps the best ratio quality/price I've seen, but here again the documentation really sucks, the app is bad and also I haven't tried it on a QS273 motor, only on smaller QS205 so I don't know for sure it works well bith big hubs.

I had great experience with the Sabvoton 72200, the app is very user friendly, it works well and the documentation wasn't too bad. But they aren't as punchy as the other two controllers I mentionned and some people complained about reliability (personnally I had no problem with mine).

So All in all there isn't a controller I'd 100% recommend. I'd go with a Fardriver if I were in your shoes, but I can't say for sure it is still the best option today.

I see you like the bms you have and have also been through many controllers in testing. I guess the only thing will be to upgrade the motor in the future so should I size the controller and everything now for the 6000w motor like you have on your Ninja?

Yeah it's always a good idea to get the most powerful controller you can afford. If you don't use it at maximum power then it won't heat and it will be more reliable. And it leaves you with the possibility of upgrades later on.

I cant find any BMS' with 600amp /1000amp peak 26S. I think that will be hard.

The 300A ANT does around 600A peaks so that's fine.

26.5 inches long will be hard to fit as well I think.

The battery you linked is a 26S 3P. The one I use is 24S 2P, so that's a lot less cells, which is a lot smaller. Maybe I'm wrong but I don't think you can fit 3P in your frame, that would be surprizing. Try to ask the seller if they can make you a 2P setup. Mine was able to do it.

 

[ElectricGSXR]

Great info as always my friend thank you. I will ask them tomorrow or whenever the contact me back. I already messaged them about shipping costs and everything so I will just wait.

 

[Chalo]

If I may, it's certainly not easier, cheaper nor more reliable to add a separate board than just use one that features it in the first place.
I'm yet to see a balancing board go wrong on an ant BMS, not saying it isn't possible but I havent heard of this failure mode in the many years I've been using them, so I wouldn't say it's something that happens a lot.

My point is that if your pack can't be overcharged, overdischarged, or pushed out of balance, why would you want other functions that are only for cutting off the power? Nothing good can come of it. That's battery overmanagement, not battery management.

 

[Dui ni shuo de dui]

My point is that if your pack can't be overcharged, overdischarged, or pushed out of balance, why would you want other functions that are only for cutting off the power? Nothing good can come of it. That's battery overmanagement, not battery management.

Sorry but I've got no Idea what youre talking about. Balancing doesn't ever cut the power , it just slows down the charge for the cells whose voltage is above the others, by creating a path for charge current to go through a resistor.

It helps your pack stay in balance every time you charge, which in turn helps spreading the load better on all cells during discharge, helping them last a bit longer. There's litterally nothing wrong with using it as often as possible, except maybe a very marginally increase power consumption during charge, and that's really nitpicking (a few Wh, maybe?).
I've used it everyday on all my motorcyces for the past 6 or 7 years now.

Saying that your pack can't be overcharged, overdischarged or pushed out of balance is a very big "IF". You cannot monitor it during ride as you physically can't keep an eye on the voltage level of every cell at once while keeping an eye on the road. You cannot monitor it during charge either, unless you stay there the whole time watching it? The only thing you can do is to monitor manually before and after every ride, which is something tedious, involving lots of self discipline and prone to human error.
If every single vehicle manufaturer chose to implement this system on every of their products it is for good reasons.

Individual cell voltages tend to rise very quickly during the last few % of the charge. If your cells are not in balance or if they show some variation in internal resistance one cell can reach its maximum voltage way before the others. If your BMS does its job, then it will cut the charge, but the other cells might not have reached 100% just yet. Repeat this cycle many times and the discrepencies will keep on increasing. With passive balancing this first cell charge speed will be slowed down, which leaves time for the others to catch up.

We're not in 1982, BMS technology is pretty much mastered by now. You don't seem to have ever tried any of those BMS systems yet, so I respectfully suggest you get your hands on one first. Then you'd know that cutting power when we are talking about passive balance charging don't make sense in this situation

 

[ElectricGSXR]

I am getting a quote on the battery shipping now but bad news they cant modify it for me. I don't know if I will be able to get it at 26.5 inches long. I'm going to head out to the garage and tinker around to see if there is any possible way but I am having doubts. That is definitely the way to go w/ the automotive grade cells. If this doesn't work out I will keep looking in that direction. Thanks again.

 

[ElectricGSXR]

So... there is no way I can even get a 24in in there. I have about 22in diagonal. 18in straight up and down. Won't fit laying down either as I only get about 18in there too. 26.5in is just too big.
Your bike must be a little bigger or the space for the battery must be.
The only other thing I can think to ask is that since you have the battery you might know... Would it be very hard to reduce the overall size of the battery pack from 26.5in from them down to the size that can fit my bike? Or is that something you wouldn't have a clue about because If you think it can be done and it isn't too crazy that could be an option.

 

[DaLanMan]

The issue that I see it most likely the amperage of the cels, If you were using 3500mAh cels you would not need as many to hit yuour uyltime mAh goal for longevity.

But past that, if you fit an XxYp cel in the space once, it can be done again, it is a common meeting point round here to have someone struggling until one of the more experienced folks wanders by and taps them into the right groove. More information is gonna be needed, what is the spec on your baattery, what is the size/shape./etc. You are asking :" can someone help, I need to meet 3 parameters with a new battery build, but they said no. Can you tell me what to do" the answer is, ask much more complete questions and you will be simply amazed at the level of responsiveness that is common around here. Because the best skill I have in this world is assembling batteries, I still suck at it but I do crank out a few a week. What you are saying makes no sense unless it is in a non-negotiable constraint (like thy have to buy someone elses case or something.)

 

[Chalo]

Sorry but I've got no Idea what youre talking about. Balancing doesn't ever cut the power , it just slows down the charge for the cells whose voltage is above the others, by creating a path for charge current to go through a resistor.

I'm talking about the difference between a balance board and a BMS. The difference is that the BMS has a set of rules that will cause it to cut the battery off, and a balancer doesn't. So if your whole system is already managed by the parameters of its components, then having a BMS that can decide to cut power or charging is only a liability, not a help.

 

[floydr]

Could you cut the series connection between13 and 14 giving you 2 13s3p battery pack each approximately 13.5", 343 mm long and then find the space to fit all 26s3p into frame or split the battery pack into whatever sections to fit the battery into frame?
Later floyd