Lipo Charging questions!....

[wadsy]

I have an RC car which uses a 4s (14.8v 6500Mah 75/150c) Onyx battery, with a Sky T200 charger. I'd been advised by the chap at Onyx who I bought the battery from to do a "storage" charge for the battery after use when putting it away when not in use for a while. I believe the (T200) charger puts each cell voltage to 3.8v for "storage". And then, when I want to use the battery, charge it to 4.2v per cell.

Now, I also have much smaller Lipos for my airsoft aegs: Nuprol 3s 11.1v 1100Mah 20c. I carried out the same charging/storage charging procedure as above (but for 3s), but at some point one of these has gone "poop" ie. It's gone fat and squishy!

I've also been advised that I should fully charge these airsoft Lipos before putting them away. So, I'm confused, what's the correct procedure(s) for charging/storage?... as I've been given differing advice!

Cheers

 

[Rogerborg]

Nuprol

For one, I'd advise avoiding that (re)brand. Nuprol chargers are notorious for going bang, and while they'll just be rebanding generic cells, they'll be the very cheapest they can source.

On storage, there is a physics-based argument for storing at about 60-70% (3.7-3.8V), so you were doing the right thing by trying it.

Personally I don't bother though, unless I suspect that I've run a battery very low by forgetting to swap at lunch. I just leave them as they are after each game then top them to 4.2V the night before the next. Lithium is pretty forgiving, I've found batteries and cells that I've misplaced for years and got them back into service, sometimes by jumping them directly to give them a quick boost to the point where a charger will finish the job.

Given that an airsoft battery costs about as much as a bottle of BBs, eking every last charge cycle out of them isn't something that really concerns me.

 

[Colin Allen]

I have an RC car which uses a 4s (14.8v 6500Mah 75/150c) Onyx battery, with a Sky T200 charger. I'd been advised by the chap at Onyx who I bought the battery from to do a "storage" charge for the battery after use when putting it away when not in use for a while. I believe the (T200) charger puts each cell voltage to 3.8v for "storage". And then, when I want to use the battery, charge it to 4.2v per cell.

Now, I also have much smaller Lipos for my airsoft aegs: Nuprol 3s 11.1v 1100Mah 20c. I carried out the same charging/storage charging procedure as above (but for 3s), but at some point one of these has gone "poop" ie. It's gone fat and squishy!

I've also been advised that I should fully charge these airsoft Lipos before putting them away. So, I'm confused, what's the correct procedure(s) for charging/storage?... as I've been given differing advice!

Cheers

It is good practice to take the batteries to their storage voltage (around 3.8v per cell), so the advice from Onyx was good.  I do it with our batteries; it isn't exactly a hardship.

Nuprol batteries are not very good, to put it mildly.  Vapextech are better, but I really like the Turnigy ones, except when they refuse to come out of battery compartment that they went into so easily, but that is another story!

 

[The_Lord_Poncho]

Vapextech are better, but I really like the Turnigy ones, except when they refuse to come out of battery compartment that they went into so easily, but that is another story!

CM098/Cyma SR25 - i'm looking at you.....

 

[concretesnail]

Use the charger to bring lipos to storage voltage, best practice safety wise and makes charging before. A game quicker.

The battery that has bloated, that's done, replace it.  But don't replace it with something that has nuprol written on it.

 

[Sewdhull]

Ive used alot of turnigy batteries over the years and they have been great. ive got some nuprols and they have been ok, but clearly a lower standard of battery ( not sure it matters for airsoft tho)

Its not a good idea to store lipos at a low state of charge, but stored full they will just lose charge over time without any immediate issue. So charge your lipos after use, full or storage level...

Ive used storage charging if im storing them.. ie for weeks or months, but not when they are in used weekly etc. Storage charging is just less stressful for a battery in the same way charging to 80% for normal use is less stressful and gives alot more cycles ( like a LOT more cycles) Ive got some life batteries that i have been using for years, 8 to 10 years maybe and they are still servicable, but they have lived a low stress life.

 

[wadsy]

Where do you guys get your Turnigy batteries from?... I'm not having much luck!

I'd ideally like to get as close a size as possible to my existing ones at approx: 100x20x16 as that's a tight enough fit as it is!

Cheers

 

[Rogerborg]

https://hobbyking.com/en_us/batteries-chargers/batteries/lipo.html

 

[Sewdhull]

https://hobbyking.com/en_us/turnigy-nano-tech-1000mah-3s-20-40c-lipo-airsoft-pack.html

maybe a lil fat?

 

[wadsy]

I bought the last one of these in UK stock...

https://hobbyking.com/en_us/turnigy-nano-tech-1000mah-3s-20-40c-lipo-airsoft-pack-t-connector.html

I did want to get two, but thought I'd grab it as it was the only one!

Cheers