A lot to ponder, I need help deciding!

[markz]

My main goal is to find a proper battery pack for a dual setup I want to do. Because I cant afford a big battery pack right away, I want to do it in 2 stages.
I will explain later. There is a lot of thinking out loud, so its a long post. Any help in deciding would be greatly appreciated. Thanks
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Lyen 18fet 65A
http://endless-sphere.com/forums/viewtopic.php?f=31&t=16605
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First off, some basic questions.
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I got a question, to increase discharge rates, do I increase Ah in the pack by paralleling.
So if theres a specific C-Rating (Constant and Peak), I go C-rate(peak) times Ah, gives me Max Discharge Amperage of batteries/battery pack?
Likewise with C-rate constant x Ah = Max Constant Amp Draw?
The formula I was using is (C-Rating) X (AH) = Maximum Constant Amp Draw
If the C-Rating stays the same on battery packages, then all I can do is increase Ah to increase max amperage.

The reason I ask, is because I've been eye'ing the BMS Batteries, which states on their High C Li-Ion, 30A cont. and 60A max.
So by putting 2 in parallel, is the discharge rate then 60Acont. and 120Amax? Or is it dependant on C-rating which they do not give.
All they give is a continuous discharge rate, and a maximum discharge rate. Another set of battery packs are rated as 50A cont. and 100A max.
This then begs the question, if these have BMS's, I put two seperate ones in series.... then the BMS's would still limit the current at 30A/60A or 50A/100A.
Because wouldnt the amperage of the first pack, add to the second? Thus the one of the BMS's would kick in, limiting the current to 30/60 or 50/100 depending on BMS?
If these packs did not have BMS's, then would my "theory" hold true?
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On my MXUS 3000W v2 4504, I want to stay away from the 96V mark for safety reasons primarily and run, in the end, 72V or 84V(mods maybe required on the Lyen 18fet for 84V) with two 36V of the same Ah from BMSB in series for 72V. Or 48V+36V in series of same Ah for 84V.
Will serializing these packs be a problem? This relates back to previous question.
In the end, I want to get the most out of my ebike.
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So as for battery packages, which I want to buy sooner then later;

Their regular shrink wrap packs are 15A cont. and 30A max. Which are dirt cheap, but too low an amperage for me.

Next in line are the "High C-Rate Polymer LiFePO4" which are 30A cont. and 60A max. This set, doesnt have a cell (name/#) attached to it. Just Polymer LiFePO4.
48V these give me 1440W cont. and 2880W max. (Just one 48V pack)
72V these give me 2160W cont. and 4320W max. (36V + 36V)
84V these give me 2520W cont. and 5040W max. (48V + 36V)
96V these give me 2880W cont. and 5760W max. (48V + 48V, but like I said 96V might be a bit too much as far as safety and speed goes, but speed is controlled by CA)
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Specs/Prices for 30A cont. and 60A max. packages...
48V10Ah $259 https://bmsbattery.com/ebike-batter...-pack-battery.html#/voltage_capacity-48v_10ah
36V10Ah $209 both "shrink wrapped this one and the above one" <^Both of these do not come with a charger.
High Rate 48V 10Ah in Case $319 https://bmsbattery.com/ebike-batter...fepo4-alloy-07-case-battery-pack-battery.html
The one above comes with a S180 charger, at 48V is 3A.
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Even with the (84V) its not using the full potential of my MXUS 3000W v2 4504 motor (3kw-6kw) and Lyen Controller 65A. I believe 65A to be the very max. on the Lyen 18 fet controller. I dont think I can go above 65A at all, not even pulse or a short time. Otherwise I have to beef up traces and/or upgrade resistor network for voltage regulator. Maybe even change it in the software, I do not know, I have no clue.
However saying that, these battery packs are well within the specifications of my Lyen 18fet 65A controller. With no mods to do at all.
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I'm not a speed freak, but I do love torque for climbing hills. I could decrease the diameter of the wheel......or.......
So if V=Speed, then is A=torque?
I might have to go and find that thread where John in CR was talking about that. It escapes me now.
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BMSB do sell a battery pack, rated at 50A cont. and 100A max, but its a little more expensive, ~$80 for same Ah rating. This brings into question a concern, if I have the Lyen 18fet rated at 65A, then for this I will have to beef up the trace, shunt, and reprogram it via the software as per Lyens specs. Anyway here are the numbers for 50A/100A.

48V these give me 2400W cont. - 4800W max, so much more improvement over the 30A/60A numbers.
72V these give me 3600W cont. - 7200W max, this seems to be the sweet spot I think for the MXUS 3000W v2.
84V these give me 4200W cont. - 8400W max. <--Overpowered, may need to change the resistor network to avoid damage to the voltage regulator on my Lyen 18fet Controller as per Lyens specs.

48V 15Ah 40252S cells $459(Below)
https://bmsbattery.com/ebike-batter...-pack-battery.html#/discharge_current-50_100a
48V 12Ah 38140 cells $381(Below)
https://bmsbattery.com/ebike-batter...-pack-battery.html#/discharge_current-50_100a
48V 10Ah 38120 cells $323(Below)
https://bmsbattery.com/ebike-batter...-pack-battery.html#/discharge_current-50_100a
48V 20Ah 38120 $575(Below)
https://bmsbattery.com/ebike-batter...2-cells-2p16s-ebike-battery-pack-battery.html

Then there is the 38120 and 40152S LiFePO4 cells to decide on as well. I really have no clue the difference between the two.

It doesnt specifically say that the battery pack has a BMS, but by this statement

Overvoltage Protection: 42Volts for 36V battery pack; 54.6Volts for 48V battery pack.
5. Undervoltage Protection: 27.5Volts for 36V battery pack; 35.75Volts for 48V battery pack.

Can I assume that it must have a BMS?

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2 Stage explanation. To begin my serializing of 2 packs. I thought I might buy a lower wattage 36V-48V controller from BMS Battery or Aliexpress, to use on my MXUS 3000W v2 4504 motor, until I have enough money to buy a second 36V or 48V pack to make it 72V or 84V, I do not want 96V. But 72V is ideal for my Lyen 18fet. All I can afford right now is one battery pack either a 36V or a 48V battery pack in the 10-15Ah range. And I really do want to get riding again. I think ideally I start off buying the 48V in the 10 or 15Ah range, and 50A/100A, along with a 48V controller, which I can use later on for a more suitable, tamer setup. Perhaps a 1000W or 1500W Leaf or Geared. I had in my sights the bbs02 as a secondary ebike setup, but I think its too little power, the 1500W $800 motor someone sells as a bottom bracket motor looks awesome, but waaaay too much $. But thats later on, I think I have to kind of think ahead as to what I want next to save money in the end. And I think a 48V first pack is good for a wider range of higher powered (more so then average) motors. This gets me thinking, again, The 96V setup with two 48V 10Ah are looking more appealling, because I could for a 2nd more tamer ebike, have a 20Ah 48V setup for longer rides. Decisions decisions decisions. 96V kind of scares me a little for the mxus. I will keep pondering.
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https://bmsbattery.com/ebike-kit/72...imulation-sine-wave-controller-ebike-kit.html
I was thinking this one, because I can use it at 36V and 48V. But everyone they sell is a simulation, which PAS is needed so I dont know if I can disable it and everything will work fine. Or I just go and buy a 48V controller from Greentime off Aliexpress. 1000W or 1500W. Then later on, I can use that controller for a more modest motor, like I was saying.
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Plan A - Buy a either a 48V 1000W(20A) or more suitably a 1500W(30A) controller, hooked up to my MXUS 3000W v2 4504, with my CA3-DP, and the 48V10Ah 50A/100A battery pack, which I can limit the wattage by the CA3-DP.

Then when I want a more tamer ebike, buy a suitable motor, use the 48V 1500W 30A Controller, a 48V 10Ah pack. One ebike is for speed, offroad. 2nd ebike for cruising.

THEN LATER, for a 84V pack.....48V + 36V in series......I'd stick with the same discharge rates......
36V12Ah 38140 50A/100A $296 (Below)
https://bmsbattery.com/ebike-batter...-pack-battery.html#/discharge_current-50_100a
36V10Ah 38120 50A/100A $251 (Below)
https://bmsbattery.com/ebike-batter...tery-12-cells-ebike-battery-pack-battery.html
36V20Ah 38120 50A/100A $440 (Below)
https://bmsbattery.com/ebike-batter...-pack-battery.html#/discharge_current-50_100a
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36V10Ah High C-Rate Polymer LiFePO4 30A/60A $209 No charger
https://bmsbattery.com/ebike-batter...battery-heat-shrink-battery-pack-battery.html
36V10Ah High C-Rate 07 Case 30A/60A $244 No charger
https://bmsbattery.com/ebike-batter...hout-charger-battery.html#/ac_voltage-90v132v
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[markz]

I was pondering HobbyKing LiFePO4, until I read this, just now.

http://endless-sphere.com/forums/vi...1&p=1023189&hilit=Hobby+King+LiFePO4#p1023189
Ykick stating HobbyKing LiFePO4

"Forget it, unless radically changed, sags badly and doesnt deliver on labelled capacity."

Post is from March 20, 2015.

 

[dogman dan]

For me, the starting point is, whatever C rate they state, cut that in half.

For hobby king stuff, cut to 1/4. So what I mean is 10 ah of 20c turnigy stuff, will maybe tolerate 30-40 amps, not the 200.

If you want high amps on the cheap. you'll need to find a place your would build a fire to store and charge your battery, and then get some 30c turnigys. 10 ah of it will stand 40-50 amps with a tolerable voltage sag.

 

[nutnspecial]

I would have to agree about lipo c-rates.
for me:
25/35c 5.8ah turnigy on a 70a setup (12c) is working the lipo a bit hard. It works, but don't plan on using all the soc. (And also, my whole ride is 230lbs, so if it was 400lbs, the extra time spent drawing power might prove to be far too much for the single string.)
Doubling the pack to 11.6ah cuts the 70a discharge to 6c, which the batteries seem happier with thru most of their capacity.

I'm curious about what you're thinking with multiple lifepo packs. Yes, you could obtain more discharge with more paralleled groups, (double for double- but go by their continuous rate; forget about the higher rate imo), but yes, imo the bms's will not allow this without permanently reworking the packs and refitting with an appropriate bms.

Hipowercycles sells bikes and batteries that are hidraw. Maybe one of their packs would suit you?
http://www.hi-powercycles.com/high-performance-e-bikes/

PS- check out eastgem for a possible battery source in the future. They are getting setup with aliexpress, and they have much more affordable packs. Untested by us, but I'm planning on taking a chance on a frame and some accessories. http://endless-sphere.com/forums/viewtopic.php?f=3&t=70616

 

[markz]

For now, I am not using RC Lipo.
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I was thinking before, looking at the BMS Battery choices for battery packs - Its a little cheaper to go with the lower discharge batteries 30/60A. Maybe just parallel them, to get the higher discharge rates (if they are doubled, then 60/120A) if they do accumulate in parallel. Like ES member states I must half those #'s, so 15/30A in parallel gives me 30/60A?
Best to stay with 50/100A discharge numbers from BMS Battery, which would sort of put me in the sweet spot for my Lyen 18fet 65A controller. IF I decide to go with BMSB. I like the looks of Greenbikekit GBK prices, especially for Headways.
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The reason for multiple packs is I want to build the battery pack in stages, and in the future use it for multiple uses (multiple bikes a "future/possible" build of a 48V "Cruiser" bike, and my current MXUS 72-84V "High Powered" bike) which I will use 48V pack on. Right now I cant afford to drop a grand on pack(s), I want to spend $350 for a 48V 10Ah or 15Ah. Then in a few months, I will buy another pack.

This is my first ebike, so I have the MXUS 3000w v2 which is a high powered motor, I liked it with my previous RC Lipo hardcase batteries, but those are gone now. I bought the Lyen 18fet controller and is suitable for 72V or 84V+ and 65A and has a 62.6V cut-off. To by-pass this using the 48V pack I am about to buy, I am going to buy a Greentime 48V-84V 45A controller for $31 to "stand-in" for my Lyen (For now). This means I can buy a 48V pack, use the Greentime controller hooked up to my MXUS 3000w v2, and the CA, so atleast I can be able to ride the bike, until 6 months down the road I can afford another battery pack. By that time it will be winter.
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I was thinking about the statement I made about the packs with BMS's, in series. That only adds Voltage, Ah stays the same, so it doesnt really matter what the BMS's are in series, as long as the packs are both the same, in terms of chemistry, Ah, C-Rating, BMS's and NOT voltage. So when I start putting packs in parallel, the amp's from each string, flows away and not through the opposite string. So once I get to the stage of increasing Ah (putting packs in parallel), its good to know that my discharge rates will increase. This of course will be a year away. Like I said the second battery after this 48V one, will be either a 24V or 36V, to achieve my 72V or 84V final voltage for my final setup of my MXUS 3000W v2.
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With all the battery packs I see, they never state no Discharge C-Rate. Only an Amperage value for Continuous and Pulse/Max.
At BMS Battery, they MIGHT state what form the cells are 18650, 38140, 38120, 40152 etc. So I guess from that I can track down from different websites what their actual C-Rating is.
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I've now been looking into Green Bike Kit for battery packages. Very reasonable prices I see. All I really look at when I view these websites are the Voltage, Ah and the Continuous and Max Amperage values. And of course if it has a BMS. The chargers they supply are usually very low Amperage (3A maybe 4A), I will try to buy a pack with a low amperage charger, and instead buy a higher amperage charger. The highest I can afford.
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So the question(s) that comes my mind.
For a final setup for the MXUS 3000W v2, I should be looking for the 50A cont. and 100A max.?
Or, is a 25/50 or 30/60 sufficient to use the motor to spec (3000Wcont. 6000Wmax) at 72V or 84V.?
The numbers I posted in the first post, suggest I need the 50/100A batteries.

I will just assume my math is correct and go with the 50/100A batteries if I choose to buy from BMSB.
Its looking more and more like GBK though.

From a quick search, all I could find was one guy who bought from them, said he didnt have a problem.
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From the looks of it, these LiFePO4 batteries from GBK do not come with a BMS.
Greenbikekit prices.....

48V15Ah, shrink wrap, Li-Ion, 20A/40A, BMS, $306.
http://www.greenbikekit.com/48v-15ah-shrink-tube-lithium-battery.html

40152 Headway battery 48V15AH $410 - "Max discharge current: 10C(150A) at 10sec." (So half that #)
http://www.greenbikekit.com/headway-48v-15ah-40152-lfiepo4-pack.html

My #1 Choice
$286 - 38120 Headway 48V10HA lithium battery - "Max discharge current: 10C(100A) at 10sec" (SO half that #)
http://www.greenbikekit.com/48v-10ah-headway-38120-battery.html

My #2 Choice
$339 - Headway battery 48V12AH made by 38140S - "max discharge current could be 120A and max charging current could be 60A."
http://www.greenbikekit.com/48v-12ah-headway-38140-battery.html

The headways look decent at 150A pulse 10sec. So again half that #, 75A is still good for me.

I will keep looking, but atleast I am narrowing down the websites to buy from.
#1 Choice - Green Bike Kit
#2 Choice - BMS Battery

 

[Ykick]

It’s always much more helpful and realistic to include shipping charges with any component price quotes. Particularly, BMS Battery, GBK.

As you now realize, a person can also get by with much cheaper, safer, lighter duty battery if they refrain from assembling and operating mini-motorcycles.

 

[markz]

That is true, thats what this mxus build feels like when I rode it on RC Lipo.
Just crazy fast! But I guess thats good in a way, and also bad.

Looks like GBK has a 50/100A option for their LiFePO4's, which is bulkier and heavier then the Samsung/Panasonic cells.
Ouch!!!!! You are right Ykick, GBK wants $100 for 4-6 day delivery. BMS Battery is the same price for similar V & Ah.

Maybe I will revert to my new find - Lunacycles, they seem to have some good offerings as well, atleast we are on the same continent!

edit: $45 for their s/h, I am sold!

edit: So, as far as I can tell, by batteryuniverse.com, is, it holds true, paralleling will indeed increase my amp flow (Acont and Amax) - Doubling and tripling it actually. With each parallel string thats added. So to save money, this package here looks promising.
http://lunacycle.com/48v-samsung-18650-battery-pack-10ah/ they state the cells are Samsung 26f 18650. For $280 plus $45, its cheaper then GBK & BMSB.
They are not the higher discharge 25r, buts its well affordable. I think I will buy this battery.

I just need an appropriate controller now, GREENTIME 15 Mosfets 48-84V 1500W 45Amax Dual mode Sensor/Sensorless Brushless DC Motor Controller its $31 + $13s/h.
This controller will do for my mxus3000w v2, until such time as I can buy another battery pack to suit my Lyen 18fet 65A 72V controller.
THEN I can use this Greentime on perhaps a geared motor like the MAC from EM3ev. Or the Leaf 1500W DD.

 

[999zip999]

You Need a cycle analyst so you can control your amp draw. Before you buy a battery, so you can turn Down your controller for an amp draw of 25amp. and check the amp spike at that level. First.
Batteries on the cheap don't last with that controller.

 

[markz]

I do have a V3 Direct Plug Cycle Analyst for any DD motor.
Thanks for the headsup, so I do not need to buy no Greentime controller, just use my CA to reduce the amps.

Thanks

 

[999zip999]

My 12fet 40amp controller runs at 44amps now, with 75amp spikes.
With that controller I get a stronger battery.

 

[markz]

Even if I want to parallel the weaker packs, in the end, to increase the max amps?

It makes sense, I found this one here
52v TRIANGLE Samsung INR18650 25r 52v 12.5ah HIGH POWER for $435.00 + $45 s/h to Canada.

http://lunacycle.com/52v-triangle-samsung-inr18650-25r-52v-12-5ah-high-power/

The Samsung INR18650 25r is one of the most respected high performance cells on the market, putting out high amps and at still a 2500mah capacity. For high performance electric bikes you cant go wrong with the 25r. This pack was designed to put out 100amps and not even get warm.

It is a high power BMS which will allow the pack to put out 50amps continous (2500 watts) and 80 amp bursts (4000 watts) alhtough running this much power will drastically reduce packs life expectancy so we recommend to not run your battery to hard if you expect it to last over a couple hundred charges.

That pack was my second choice, for the reason you just said.

Thanks

 

[999zip999]

It would work if you aren't running up to long or steep of hills, no mountains. Do you want to run 48volt ? A battery is a investment. Investments cost money. Can't get around battery money.

 

[markz]

I am sold on the 48v Samsung INR18650-25r 12.5ah HIGH POWER for $365.00 +$45s/h. Will also buy their 5A charger, and velcro trianlge bag.
The 52V Samsung INR18650-25r 12.5ah HIGH POWER for $435 is only 10 cells diffence and $70, which judging by the sellers of these cells, cells sell for $7 each.

Again though, my Lyen 18fet Low Voltage Cutoff is 62.6V.....I can change that can I, in the software?
I have been unable to download, unpack and install software to be able to do this.
I have tried multiple times, just now even. Doesnt work.

Leads me again to buying the 48V Greentime controller

 

[Ykick]

MAJOR feature of Lyen controllers IMO is the ability to program. You owe it to yourself to figure that out. Board versions may have changed which can complicate things but it’s really worth the trouble it get it to work. You’ll be glad you did.