pawraith

can anyone tell me what the expected life of a lipo is and why i'm losing some of my capacity? i'm running a thunder power 2200 3s that i balance with every charge. i probably got at least one flight a day for the past 3 months and ive dropped to about 1750 mah. there is no swelling and the batt temp isnt any hotter after a flight then when i first started using this battery.

cflight

Pawraith, heat is the number one enemy and affects the middle cell the most. Overdraining the capacity is also a cause of the bat. loosing it's ability to retain a full charge. Stick to drawing less than 80% of the Mah. I've noticed that ballance charging my bats repeatedly, first charging at 2A then topping off a couple of times at 0.2A, has put back some of the voltage imbalance that was developing. The worst one read 4.15, 4.09, 4.18, and took several charges at 0.2A to bring it back to 4.18, 4.17, 4.18V , this is as good as I could restore the voltage. I've read that the voltage between cells should never differ by more than a tenth of a volt, which had me a little conserned when it took several charges to raise the middle cell above 4.09. From know on I'm going to keep an eye on each cycle for individual cell voltages differing and recharge at 0.2A repeatedly until I'm sattisfied it will take no more. Good Luck

Zoea

Hi I hope you don't

mind me borrowing the thread here ....

.. I wonder if anyone could help with a problem I'm having with some 2s RC Car Lipos? I have one which is a 5600 mah 20c pack, which will only accept 2600 from a storage level charge. That seems lower than it should be (and was some time ago).

It's had long periods of unuse and is about 2.5 years old, though has been stored at storage charge (circa 7.6v) and checked once or twice since purchase. It really got minimal use, <5 run

Also, I have 2 trackpower gold I purchased 2nd hand at around the same time. They now take around 1600 from storage voltage only (very estimation). They've been in the same situation.

Finally, I have 2 no-brand 10c 5000 2s LiPo cells, they aren't doing so well, one puffed up and the other takes a low charge, something around 22.2300 from storage voltage before the charger senses it should stop.

So, of all 5 of my batteries, I have completely none that I'm happy with. This is only 2.5 years since purchases!

I have read somewhere::: that I can freeze them or something, to be honest I don't really believe that'll work since I've read it won't help. I thought I should be able to do something with cycles of charge - discharge - charge or charge - settle to storage voltages - charge, however ,,,, I wanted to know if anyone has actually been in a similar position with a LiPo and retrieved some precious milliamps * hours capacity for their future usage.

Much cfe appreciated, many thanks.

Solman

To the OP, did you leave them fully charged between flying days?

To Zoea, it would have been better if you started a new thread. Also you posted about cars on a heli forum. I would suggest going to a car forum and ask there.

gimbleguy

I always charge my lipos at 1C, they last a long time. 90-95% efficiency. High C rating lipos(ie: 70C ), I personally find that holds their charge well.

Solman

Do yourself a favor. Don't buy no name brands. You are almost guaranteed to end up with junk. I know that from experience when I did that one time. Second, buy batteries that are at least 30c. Anything less is too easy to end up being abused.