LifeBatt cells now available for ebike use

[recumbent]

:| I can read "14AWG" on the bottom, right side, black wire, just use magnifier on your computer.
This is why having a shunt like the Cycle Analyst system is best.
I'd like to measure the resistance, if any, from using a Wattsup meter, so we know for sure.

 

[OLIVIER]

Since the idea behind electric vehicle is mainly to be more "clean", what is planned for all the Lifebatt cells when they are at the end of their life cycle?. Can they be recycled?

 

[Battboy]

Yes, LiFePO4 is a re-cyclable battery chemistry.

Don Harmon

 

[GGoodrum]

Hey Gary, that's a very interesting test you did. i was wondering about weight and energy between chinesse and A123 cells..

I bet the match with a charger like teh one i'm building would be awsome!

My final calculation give me a charge current of 17A per parallel cell group for the A123 and 15 for lipo or 18650 that are 4.2V charge.

17A for a 10Ah would cahrge completly your bike in less than 40minutes !

Doc

Each a123 cell weighs about 75 gm, I think, and is 2.3Ah, so that is 32.6 gm per Ah. The LiFeBatt cells are 365 gms and 10 Ah, so 36.5 gm per Ah, which is pretty close.

From what I can tell, they can be charged exactly like an a123 cell, so whatever works for one, will work for the other. I think the max charge rate is like 30A, so your 17A individual cell charger would work fine.

 

[GGoodrum]

Our "Watt's Up" WU100 and Doc Wattson R102 meters use AWG 14 or heavier gage wire and high temperature silicone insulation.

That quote is from this page:
http://www.rc-electronics-usa.com/meter-faq.html#faq8

ARe you sure tose are 10 guage wires? Where can I get the one with 10 guage?

No, the meter itself has 14-gauge wires, but I trim them short, and use 10-gauge wires leading to and from it. If you hook it up as shown in the first option below, only the negative lead needs to have heavier gauge wire:

All I know is I can't tell if the meter is connected or not, the power feels exactly the same, so like I said, I don't worry about it.

-- Gary

 

[GGoodrum]

Question for Bob and Gary on the charger - how far are you in the process of designing the new charger ? I am asking because I've started working on my own switching 1C charger along the lines of ideas that I've posted here recently. I already have it running in Spice simulator and ready to start working on a PCB. I planned on making the PCBs or even kits available at cost for the community. However if you already have something that will charge LiFePO4 cells individually at about 1C rate in more advanced stages of the development I'd rather spend my time on something else. Alternatively I can offer my help with your design. Please let me know.

Prior to discovering you plans for the dedicated charger I wanted to ask you make LVC output available on the balancing connector to avoid replicating this circuit inside the charger - my circuit uses it to reduce the charge rate until all cells are above LVC threshold. What connectors do you plan for balancing plug ?

Bob is working on the design right now for a "CMS" board that basically can go between any suitable CC source and the pack. It will bulk charge at the max rate of the supply/charger until the cells start getting to 3.65V and then it will switch to an individual CV mode in order that the voltage is held at that point, and the current for each cell will be allowed to drop to the point that the cell is completely full.

The CMS will connect to the packs via a single multi-wire cable with a high-curret Molex connector. Conceivably, this Molex connector could be used with individual cell chargers as well, depending on the max current.

I'm not sure why you would need the LVC outputs, as they are used to detect when a cell is too low. I think Bob is planning on using similar voltage detectors to sense when the cells first hit the cutoff, which is 3.65V.

-- Gary

 

[curious]

Gary -

The only reason to have an LVC input to the charger is to start CC mode at a lower than normal rate in case a pack has cell that is below LVC threshold - pretty much like a lipo revival process. I am not sure it is really needed but it comes at little cost to the charger design and offers a bit of extra safety.
The charger I am working on now is a self contained switch mode 350W AC unit (12V version can be done as well) that has 10 outputs for individual charging at ~10A (can be easily tweaked to 12s at this stage). Should be relatively portable (few lb). I have no plans to commercialize it but possibly providing PCBs for it.

If you think it makes sense I'll keep going with the design - I just do not want to replicate someone's else effort.

 

[efreak]

Hi Curious, I am curious is that Diy design and any pics ??

pleas e and thank you
I am currently contemplating a trouble free solution thats easy and reliable so like a dc power supply and need all the help i can get in this thanks.

efreak

 

[curious]

Check my thread on DIY A123 multicharger in the battery technology forum. This thing does not exist yet except in the Spice simulator. I just need more feedback before committing further time to the project.

 

[Patrick]

See the post in Selling and Surplus for a better price.

 

[kbarrett]

The CMS will connect to the packs via a single multi-wire cable with a high-curret Molex connector. Conceivably, this Molex connector could be used with individual cell chargers as well, depending on the max current.

How many individual cells / cell packs will your CMS service?

If I were to use it with an A123 pack, should I be thinking a series of 10, 11, or 12? ( 33V, 36.3V, or 39.6V? )

How many individual 3.3V leads will there be on the Molex connector? What will the pinout be?


I am in the middle of building my first A123 pack, and would like to avoid dissassembling it in a few months.

 

[GGoodrum]

The CMS will connect to the packs via a single multi-wire cable with a high-curret Molex connector. Conceivably, this Molex connector could be used with individual cell chargers as well, depending on the max current.

How many individual cells / cell packs will your CMS service?

If I were to use it with an A123 pack, should I be thinking a series of 10, 11, or 12? ( 33V, 36.3V, or 39.6V? )

How many individual 3.3V leads will there be on the Molex connector? What will the pinout be?


I am in the middle of building my first A123 pack, and would like to avoid dissassembling it in a few months.

The current LVC board I'm using for the 12-Cell and 16-Cell LiFeBatt packs will accomodate up to 16-cells. We are using an 18-pin Molex connector that will have a matching Molex plug attached to the CMS unit. The idea will be that you plug your charger into the CMS, and then connect the CMS to the pack via the Molex plug.

I don't have the exact pinout yet for the Molex plugs, but PM or email me (ggoodrum@tppacks.com) and I'll let you know later. As long as you bring the wires out now, you shouldn't have to rebuild you pack later. Just make sure you use wires big enough to carry 5-10A. I think 16 or 18-gauge should be fine.


Bob and I are still working the CMS details. the plan is that the design will be modular/scalable, and will allow each cell to individually receive a full charge, independently from the other cells. What I'm not sure yet is at what the maximum charge rate will be, but it will be at least 5A.

The packs are basically available now. They will come in two versions, a 12-cell 40V/10Ah pack, and a 16-cell 52.8V/10Ah pack. Both will come pre-installed with a fully assembled and tested LVC board. There will be three cables/connections on each pack, a set of main leads that are 12-gauge silicon wires with a female Deans connector, a 2-wire JST female plug to connect to the controller's brake inhibit line, and the multi-wire harness with the 18-pin Molex connector that will interface with the CMS unit.

The price for the 12-Cell pack is now going to be $575, plus shipping. The 16-cell pack price is now $750, again, plus shipping. I should have both packs listed on my TPpacks website in a day, or so, but if somebody wants to order sooner, you can email/PM me. With the current backlog I have, it will take about 2-3 days to actually build/test the packs, before they are ready-to-ship. All sales, including all major credit cards, are handled via PayPal. These packs will come with a 2-year warranty.

I'll post pictures of the first "production" 16-cell pack later today, or tomorrow.

-- Gary

 

[iberkt]

They will come in two versions, a 12-cell 40V/10Ah pack, and a 16-cell 52.8V/10Ah pack.

Any chance of geting diffrent versions (spacial request type stuff)? The reason I ask is that I'm Considering the Cyclone system that uses only 24v.

....humm let me think that would be 16 cells wired up as a 26.4V/20Ah pack. Oh yeah that would be nice!

 

[GGoodrum]

They will come in two versions, a 12-cell 40V/10Ah pack, and a 16-cell 52.8V/10Ah pack.

Any chance of geting diffrent versions (spacial request type stuff)? The reason I ask is that I'm Considering the Cyclone system that uses only 24v.

....humm let me think that would be 16 cells wired up as a 26.4V/20Ah pack. Oh yeah that would be nice!

That would be a special order item, but yes, we could do that.

 

[disndat]

Hey Gary whats going on with the chargers?Also I guess you are not into building A123 packs?

 

[RevDon]

Hey Gary whats going on with the chargers?Also I guess you are not into building A123 packs?

And please start posting in the EV Business World Forum!

 

[GGoodrum]

Hey Gary whats going on with the chargers?Also I guess you are not into building A123 packs?

What Bob and I decided is that initially what we will do is to create a "Charger Management System" (CMS) board that will use any suitable bulk charger or regulated power supply as an input, and will have individual connections to each cell, via the Molex connector. It will allow each cell to independently get a full charge, everytime.

Although a123-based packs perform well, they are a royal pain to build into suitable ebike packs. Way too much labor involved, for me.

-- Gary

 

[deecanio]

Hi Gary,

Hows the cms board coming along, still very interested in getting a custom pack from you but waiting until i know you guys have cracked it and i can just plug in an recharge knowing my cells are all balancing nicey.
keep us informed!!!


Cheers


D

 

[GGoodrum]

Hi Gary,

Hows the cms board coming along, still very interested in getting a custom pack from you but waiting until i know you guys have cracked it and i can just plug in an recharge knowing my cells are all balancing nicey.
keep us informed!!!


Cheers


D

Bob is testing the first prototype right now, so it shouldn't be too much longer. As soon as I get one to test, I'll post some pics.

-- Gary

 

[RA]

Will the Low Voltage and CMS boards be available as a kit?

Ron

 

[GGoodrum]

Will the Low Voltage and CMS boards be available as a kit?

Ron

Yes, once I get the packs really into production, I'll also release a kit that includes the LVC boards.

The CMS is a separate unit, but because of the complexity and testing requirements, we probably will not offer these in kit form.

-- Gary

 

[GGoodrum]

Just a quick update on the CMS...

Bob has been busy, testing the prototype CMS unit. So far it seems to be working fine. He just has a couple of minor tweaks and then we should be able to get these going. Within a couple weeks, is my best guess.

Here's what the 16-cell 48V/10Ah pack looks like:

This is 13-1/2" x 6-3/4" 3-3/8" and weighs 14 lb 7 oz.

-- Gary

 

[Battboy]

Do they make a clear shrink ???? Would be nice to see the beautiful workmanship that goes into these packs!

 

[Johnbear]

That is a nice job with the heavy shrink wrap. Clear shrink for that pack would be nice!

 

[Doctorbass]

Just a quick update on the CMS...

Bob has been busy, testing the prototype CMS unit. So far it seems to be working fine. He just has a couple of minor tweaks and then we should be able to get these going. Within a couple weeks, is my best guess.

Here's what the 16-cell 48V/10Ah pack looks like:

This is 13-1/2" x 6-3/4" 3-3/8" and weighs 14 lb 7 oz.

-- Gary

Great work Gary and Bob!

I found that you are conservative about the voltage. 48V for 16cell is at 3V per cell instead of 3.3V so i suppose that you say 48V when a big load is applyed? right? maybe 40A.. 60A to drop to 3V?


Doc