Originally Posted by rcbobp

I use the Hitec chargers and balance charge all the time at 1c (2.5 amps for 2500 batteries), but it's taking up to an hour to put in 1,000 milliamps. Starts off real fast, but then it spends about 30 minutes or so balancing out the last .2 amps between the two cells. Seems to be the problem for all my A123 batteries. Any chance it's the charger? What chargers are you using out there?


Thanks.

I don't see any reason to balance charge authentic LIFE batteries "all the time".
I do balance charge them, but just once in a while, and when I do, the readout shows them to be pretty close anyway.


I use the Hitec X2 AC Plus Black Edition, and normally charge at 1amp for my 2S, 2500mah packs.
These are packs I built myself.


They could take twice that with no penalty, but I take 3 packs with me to the field, and I have yet to even have to charge them at the field.


LIFE 2S packs are the best thing that ever happened to people like me who fly glow/gas.
I had used NiMH 5-cell packs for years, but these direct replacement 2S LIFE packs are so much better and I will NEVER go back to NiMH.

Originally Posted by Carter

I don't see any reason to balance charge authentic LIFE batteries "all the time".
I do balance charge them, but just once in a while, and when I do, the readout shows them to be pretty close anyway.


I use the Hitec X2 AC Plus Black Edition, and normally charge at 1amp for my 2S, 2500mah packs.
These are packs I built myself.


They could take twice that with no penalty, but I take 3 packs with me to the field, and I have yet to even have to charge them at the field.


LIFE 2S packs are the best thing that ever happened to people like me who fly glow/gas.
I had used NiMH 5-cell packs for years, but these direct replacement 2S LIFE packs are so much better and I will NEVER go back to NiMH.

+1

Agree 100% with everything you said.

Originally Posted by acerc

I have a Hitec charger that reads the same way. I think it is just the way the last little bit goes in. I have another charger that does the same with the last little bit it just displays different. I run LiIon and LiPo and both chemistries do the same. I was told it is such a small amount at the end I did not have to worry about it. I only charge at one amp and was also told if I would up the charge input to a minimum of 1C it would charge at a rate that would not recognize that last little bit and end the charge. In my opinion if charging at a higher input warms the battery enough to not notice the last little bit it is to high for me. Of course none of this may be correct but charging at 1C works for me, or at least my batteries last a long time.

Agree Ace. The tiny bit of charging that takes place at the end of the charge cycle is a very small % of of the overall charge. Just skipping it has little bearing on how complete the charge cycle is.

Just my own take, but I've found that when 2 A123 cells don't want to balance normally, one of them is about to take a dump. Watch for a difference in cell voltage. If they no longer match, I would have cause for concern. That pack will not have near the capacity of one that balances easily.

I use CellPro's to charge all my A123/LiFe packs, they balance charge pretty quickly.

Electro Dynamics has a nice A123 Life battery system. Batteries, switch and charge cord all designed to work together. You can charge and balance the batteries in the plane through the switch. Just remember if you have two batteries for the receiver you can't charge both batteries at the same time due to the common ground problem which applies to all battery chemistries. I have their system in all my giant scale gassers without a problem. I use only two batteries to run everything.

Originally Posted by tciranni

Electro Dynamics has a nice A123 Life battery system. Batteries, switch and charge cord all designed to work together. You can charge and balance the batteries in the plane through the switch. Just remember if you have two batteries for the receiver you can't charge both batteries at the same time due to the common ground problem which applies to all battery chemistries. I have their system in all my giant scale gassers without a problem. I use only two batteries to run everything.

Same set up I use from Electro Dynamics. Works well & has for some time now. I always watch my usage & cell balance .

Originally Posted by tciranni

Electro Dynamics has a nice A123 Life battery system. Batteries, switch and charge cord all designed to work together. You can charge and balance the batteries in the plane through the switch. Just remember if you have two batteries for the receiver you can't charge both batteries at the same time due to the common ground problem which applies to all battery chemistries. I have their system in all my giant scale gassers without a problem. I use only two batteries to run everything.

Im glad you added that I just got a hitec x2 and i was fixing to run into the issue you described. By Luck each battery has 2 leads to the receiver so im not using 1 i havent tried charging 2 at once yet just came in from the shop.

Question: How long do you all leave your Li-Fe /A123 Pack charged full for? I knew that is can be a few weeks with out any harm, But i read on the life source page that after 6 months its then advisable to storage charge?Seams like a long time.

So it would appears you can leave then at any charged capacity ie -50-100% for upto 6 months? Then is advised to pop them down to storage voltage.

Does this sound correct?

Nope doesn't matter, you can leave them for weeks, months or a year fully charged. The self discharge rate is extremely low and it doesn't hurt them a bit

Originally Posted by The Hodge

Question: How long do you all leave your Li-Fe /A123 Pack charged full for? I knew that is can be a few weeks with out any harm, But i read on the life source page that after 6 months its then advisable to storage charge?Seams like a long time.

So it would appears you can leave then at any charged capacity ie -50-100% for upto 6 months? Then is advised to pop them down to storage voltage.

Does this sound correct?

If you know that a pack is going into storage for a few months, I think it's a good plan to charge them to a partially charged level for storage - in the name of being as friendly to your pack as possible - on paper anyway.

If you don't know when you will be flying next, go ahaead and put a full charge on. The fact they'll hold that charge for months is a thing of beauty!

I've had planes I damaged and put away for a year partially charged and have had some put away fully charged for a year. No noticeable difference of any kind.

Yeah I generally leave my packs charged, and the first li-fe packs I bought many years ago are finally down on capacity. I suppose if I knew I weren’t going to use them for the better part of a year, I might put them on storage mode, but generally they seem fine with being at full charge. Different animal than li-po.

Originally Posted by BarracudaHockey

Nope doesn't matter, you can leave them for weeks, months or a year fully charged. The self discharge rate is extremely low and it doesn't hurt them a bit

Perfect thats what i thought , I remember reading it about 5 years ago but kind of forgot it. lol Thats for confirming.

Off topic, But does the Li-ion cells work much like the Li-fe / A123