Battery charging question

[Molle123]

Hello!
Yesterday finally my package with the Arrma Kraton and battery/charger arrived.

I did just charge my LiPos for the first time.
The LiPos are 3S 5400mAh 50C.

When the charge were complete the charger says 4.2 volt on all cells. That's good. But at charge capacity it says 3689mAh. Shouldn't it be on 5400mAh when battery is fully charged?

 

[chevys10zr2003]

Hello!
Yesterday finally my package with the Arrma Kraton and battery/charger arrived.

I did just charge my LiPos for the first time.
The LiPos are 3S 5400mAh 50C.

When the charge were complete the charger says 4.2 volt on all cells. That's good. But at charge capacity it says 3689mAh. Shouldn't it be on 5400mAh when battery is fully charged?

I believe that is just measuring the mah that it took the charger to get the battery to full capacity. It will only say 5400mah if you run it down to the low voltage cutoff first and most likely it had a storage charge from where you bought it so it wasn't at the low voltage cutoff.

 

[yonzariq]

Yep, when you buy it a lipo is never fully empty as this is bad for the battery as we all know.
I believe most manufacturers set them on storage at around 30% of their capacity, which this also is.
So you will probably never load 5400mah into your battery unless you have a lot of energy loss due to heat or a bad battery.

 

[Molle123]

Thaks guys, that sounds right haven't got the time to test drive it yet. Tomorrow will be the big day.
That means the batteries will be stored fully charged for about 30 hours. Will that do damage to the batteries?

 

[chevys10zr2003]

Some people will tell you that they shouldn't be at full charge for more than 2 hours while other people always store them at full charge. I myself store them with a storage charge from my charger and then fully charge them the day before and then when I'm done I storage charge them again. It really depends on what you want to do but I myself have never had a problem with charging them the day before.

 

[yonzariq]

I only charge them to storage when I know I won't be using them for a week or more
Never had any issues with my lipos this way.
Some were 1,5-2 years old and still performed and were balanced fine.

 

[Steve]

I've been storing mine fully charged in the wine fridge, between a very nice bottle of Cabernet Sauvignon and Bordeaux at 52 degrees.
So far, a bit over a year old, they balance fine and run times seem the same.

BTW, there's a great thread here, "what's you budget LiPo of choice", where guys keep piling on with new distributors at even lower prices.
A great RC resource.