# A123 20Ah LiFePO4 - has anyone experience with that cells



## Pawiel (Sep 15, 2013)

has anyone had any real practical experience with the A123 20Ah prismatic cells?
I am thinking about a battery made of these cells in configuration 30s5p. Is this a good idea?

According A123 Datasheet these cells are very safe and long-life.

If my idea (30 cell in series and 5 parallel) is logical:
- according what rules pick the right BMS and charger?
- are there any special rules to obey?

Or is there a beter choice than A123?

The batteries should power 30kW motor (100V, 100Ah ---> 10kWh capacity)


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## rwaudio (May 22, 2008)

Pawiel said:


> has anyone had any real practical experience with the A123 20Ah prismatic cells?
> I am thinking about a battery made of these cells in configuration 30s5p. Is this a good idea?
> 
> According A123 Datasheet these cells are very safe and long-life.
> ...


I wouldn't do it.... I spent a year on them and only have a small portion of a working pack, the rest is made up of CALB prismatics that perform well and were much easier to use.
Check out my blog for details.
With that said I do have an 18S4P group of the cells that work working very well, you won't actually get 20Ah out of a cell though, consider them 18.5 - 19.5Ah


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## Pawiel (Sep 15, 2013)

Thanks for answer. 
I will study your blog very carefully. You know... A123 datasheet promises miracle 
The beast way - listen to the others and learn from practice.


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## Pawiel (Sep 15, 2013)

I found this - this is probably your battery:
http://www.electriccarpartscompany....in-br-115-44-245-mm-br-44-lbs-2-kg_p_282.html



The price is a little bit bigger than A123, but looks very interesting.
What about life-time of that battery (*I still haven't red your entire blog, so if there is everything - sorry for waisting your time).


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## z_power (Dec 17, 2011)

Hi,
I'm from Poland, too  If you're considering lithium then check 3xe and ev-power.eu (clickable logos on right side of forum layout); they seem to offer best prices in our neighbourhood. If you're buying by ev-power as business customer with EU NIP (euro tax number) then you don't pay VAT.
Pozdr.
Michal


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## rwaudio (May 22, 2008)

Pawiel said:


> I found this - this is probably your battery:
> http://www.electriccarpartscompany....in-br-115-44-245-mm-br-44-lbs-2-kg_p_282.html
> 
> 
> ...


Yep, that's the cell I'm using now.
I believe they have similar ratings to most LiFePO4 2000 cycles to 80%, 3000 to 70%


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## Pawiel (Sep 15, 2013)

rwaudio said:


> Yep, that's the cell I'm using now.
> I believe they have similar ratings to most LiFePO4 2000 cycles to 80%, 3000 to 70%


For how long time (charge cycles/km...) are you using these batteries? 

Greetings.

.....
Oh - sorry. It's everythig on your Blog... I have just found it.


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## mikec5537 (Nov 11, 2011)

Hi,
I made a 6KW/H battery 16s 6p from a123 cells it works very well but was not easy to make. The cells are difficult to work with because of their format something with a ridged case and bolt connectors would be much easier. I ended up making clamps and connectors from 3mm x 20mm strip copper and fastening everything together with 5mm machine screws.

It has about 220 cycles on the pack so far and holds balance very well

Best regards


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## Pawiel (Sep 15, 2013)

mikec5537 said:


> Hi,
> I made a 6KW/H battery 16s 6p from a123 cells it works very well but was not easy to make. The cells are difficult to work with because of their format something with a ridged case and bolt connectors would be much easier. I ended up making clamps and connectors from 3mm x 20mm strip copper and fastening everything together with 5mm machine screws.
> 
> It has about 220 cycles on the pack so far and holds balance very well
> ...


What kind of BMS and charger are You using in your solution?

Greetings


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## piwhy (Feb 8, 2011)

Hi,
I'm also using an A123 home-made battery pack (6,3kwh / 32s3p) made with 20Ah pouch cells since approximately 6 months which works pretty well on my motorcycle. I've achieved around 50 charge/discharge cycles ; cells are still well balanced and I can easily reach 90% of the theorical capacity (~5,6kwh).
But I confirm that the pack assembly is the hardest task... !
Also, I don't know if today you can easily find these cells in a not too bad condition ?


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## Pawiel (Sep 15, 2013)

piwhy said:


> Hi,
> I'm also using an A123 home-made battery pack (6,3kwh / 32s3p) made with 20Ah pouch cells since approximately 6 months which works pretty well on my motorcycle. I've achieved around 50 charge/discharge cycles ; cells are still well balanced and I can easily reach 90% of the theorical capacity (~5,6kwh).
> But I confirm that the pack assembly is the hardest task... !
> Also, I don't know if today you can easily find these cells in a not too bad condition ?


Have you measured battery/cells capacity at the beggining? if yes, was the capacity the same than today?


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## piwhy (Feb 8, 2011)

Pawiel said:


> Have you measured battery/cells capacity at the beggining? if yes, was the capacity the same than today?


Yes, I've checked each cell before to assemble my pack and I didn't noticed any capacity drop until now.
But I had ordered 10% more of cells, to eliminate the weakest ones when I made my battery pack.


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## rwaudio (May 22, 2008)

Pawiel said:


> For how long time (charge cycles/km...) are you using these batteries?
> 
> Greetings.
> 
> ...


Do you have a reliable source for these cells? Many of us got them from Shenzhen Victpower with good through very bad results. I would imagine they are out of cells by now and A123 went under so I'm not sure if there are any fresh cells out there.

If you do go ahead with these (if you get good cells they really do perform well) but there are some critical assembly steps required in order to make a working pack, otherwise it will leak and destroy itself. I also have a design for cell to cell interconnect that results in incredibly low series resistance making a very high performance pack.

Good luck.


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## Pawiel (Sep 15, 2013)

rwaudio said:


> Do you have a reliable source for these cells? Many of us got them from Shenzhen Victpower with good through very bad results. I would imagine they are out of cells by now and A123 went under so I'm not sure if there are any fresh cells out there.
> 
> If you do go ahead with these (if you get good cells they really do perform well) but there are some critical assembly steps required in order to make a working pack, otherwise it will leak and destroy itself. I also have a design for cell to cell interconnect that results in incredibly low series resistance making a very high performance pack.
> 
> Good luck.


For now unfortunatly I don't have a reliable source of these cells. Of course, in my neighborhood is a company selling cells, motors and other EV stuff, but now I'm doing a little research. I want to minimize a risk of bad luck.

What do you mean exactly saing "critical assemmby steps required in order to make a working pack,.....". If you don't want to write a lot, just insert a link, if you can of course. 

For now, I still don't know what cell to chose.


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## Pawiel (Sep 15, 2013)

piwhy said:


> Hi,
> I'm also using an A123 home-made battery pack (6,3kwh / 32s3p) made with 20Ah pouch cells since approximately 6 months which works pretty well on my motorcycle. I've achieved around 50 charge/discharge cycles ; cells are still well balanced and I can easily reach 90% of the theorical capacity (~5,6kwh).
> But I confirm that the pack assembly is the hardest task... !
> Also, I don't know if today you can easily find these cells in a not too bad condition ?


So, in your opinion - most of cells are not worth buying - you think?


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## Pawiel (Sep 15, 2013)

piwhy said:


> Yes, I've checked each cell before to assemble my pack and I didn't noticed any capacity drop until now.
> But I had ordered 10% more of cells, to eliminate the weakest ones when I made my battery pack.


Hmm. Thats great. 
You made a great deal with your batteries. 
I hope, that every cell will work like in datasheet. 

With how strong currents (per cell or per battery) do you explore your vehicle? In datasheet is (as far I remember) 5C max and 3C normal...


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## major (Apr 4, 2008)

http://www.buya123batteries.com/AMP20M1HD_A_Lithium_Ion_Prismatic_Pouch_p/amp20m1hd-a.htm 

This may be a source for you. But $70/cell. You can find plenty of chatter about the cells and even sources for build kits on ES. See: http://endless-sphere.com/forums/viewtopic.php?f=14&t=38545

It makes my EnerDel modules look sweet


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## Pawiel (Sep 15, 2013)

First link - with distributor A123 - looks ok, but the price is much higher than a price from distributor in my neighborhood (Poland). 

Second link - the guy from Endless Sphere coped with that issue very well. I like it. 

Are you using A123 batteries in your designs/projects?


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## major (Apr 4, 2008)

Pawiel said:


> First link - with distributor A123 - looks ok, but the price is much higher than a price from distributor in my neighborhood (Poland).
> 
> Second link - the guy from Endless Sphere coped with that issue very well. I like it.
> 
> Are you using A123 batteries in your designs/projects?


I have participated in the build and use of A123 pouch cells on the MC you see in my avatar. But recently I have been using EnerDel. 



major said:


> It makes my EnerDel modules look sweet


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## Pawiel (Sep 15, 2013)

major said:


> I have participated in the build and use of A123 pouch cells on the MC you see in my avatar. But recently I have been using EnerDel.


I would be very glad if you tell me something more about your Enerdel? Which one of these below have you got?

http://evolveelectrics.com/Enerdel_CP160-365_Moxie.html

http://evolveelectrics.com/Enerdel_CE175-360_Moxie.html

It's not LiFePo4, it's " Hard Carbon/Mixed Oxide (NMC) ". How it work's in your EV? No problems?
How much current you drag from it and how is the whole battery configured (...s....p)?

According manufacturer, number of cycles is awsome. I hope that half of that is true.

Regards.


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## major (Apr 4, 2008)

Pawiel said:


> I would be very glad if you tell me something more about your Enerdel? Which one of these below have you got?
> 
> http://evolveelectrics.com/Enerdel_CP160-365_Moxie.html
> 
> ...


I think it is all true. And use the forum search tool for EnerDel and review threads started by me in particular. I also have an EnerDel 24kWh pack in my Think EV which I use daily and am up to maybe 400 cycles and running strong as ever.


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## mikec5537 (Nov 11, 2011)

Pawiel said:


> What kind of BMS and charger are You using in your solution?
> 
> Greetings


Hi,

Charger is BMS battery 48v 1000W
BMS - none, just monitor with cell logs. I tested every cell and mixed the good and slightly low capacity cells so all the parallel groups were almost the same. They stay in balance very well

Best regards

Mike


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