What length of disuse warrants discharging batteries?

[PropsToYou]

Hi all, I was wondering at what point I need to start thinking about discharging my batteries.
Is it recommended if they will be unused for more than a couple of days, or is it more of a week, or even a month? I have no idea!

[arturios]

I would say more than a month... Not really had to discharge my batteries as I only charge them prior a flying sess. So they are generally close to or around a discharged state/voltage most of the time anyway.

That';s my method and seems to work for me so far and no puffed lipos.

[annikk.exe]

For me personally, I would discharge and then storage charge my lipos if I knew I wouldn';t be using them for more than a week.  Also never had a puffed lipo... although I haven';t been doing this for all that long. :>

[Paul01]

Leaving lipo in a storage charge, is only beneficial if you are leaving them for months without using them. Charge them up and leave them somewhere cold as this slows down the discharge rate.

[bazzerh]

some say if you charge them then decide not to use then discharge if you';re not going to be using them within a week or so. if you';ve flown them and they are in an ok discharge state when they come down ie 3.3-3.6 then just leave them until the next session. if you';ve got excited and brought them down to 3.0v or thereabouts then charging them up is better than leaving them.

I';ve only been using lipos for about 5 years and mainly with cars but i dont think i';ve ever done a storage charge. race, chuck lipo in bag, next meeting charge them up again. thats what majority of car racers do too and they';re paying £50 for a 2 cell 

[Yellow]

£50 for a two cell what!

I';m glad you asked this, I';ve been going on about a week, but maybe I';ll be more lenient now , bit of a hastle to plan a week ahead with dodgy weather, a month of far more practical

[firey1]

my batteries over 3 yrs old never done storage charge always charged up none have puffed even my 2 li-fe batteries

[Paul01]

Leaving them for prolonged periods fully charged does not cause them to puff up, it affects the batteries usable life, but i think heat does much more damage. Lipos puffing up is caused by pulling too many amps from them and running them too low.

[pheasant_plucker]

the issue with leaving them charged is the chemical properties of the battery changes with temperature. A battery charged cold could become overcharged if it is then placed in a warm environment with all the inherent risks of spontaneous combustion etc.
I always store mine fully charged and as long as they are stored in a stable environment they are perfectly fine. Mine usually reside in my sock drawer over winter and I have cells that are 5 years old now and show no signs of failing.

Gerry

[Friskle]

My batteries are nearly always left fully charged, If one puffs, its due to being damaged, to much use or simply asked to much of it, mine are under the stairs, and in over 7 years, never had a battery fail due to being stored full, the biggest factor for storage is, if full, and something happened, then the reaction if far more volatile, than one left at storage charge, and in most cases they will only actually ignite "IF" the compound has been shorted, a puncture of the just the outer skin can sometimes be missed and the battery will still charge and be able to be used.

If you ever go into your battery storage area and smell something sweet, then one is possibly punctured, no one knows for sure what is best to do with lipos really, all you do is treat them with respect and go from there.

[jamesb72]

The issue is being able to easily and safely discharge lipos when weather is crap for flying. I can';t believe no-one sells a decent 250w or so discharger, as it would sell a boat load and can';t be hard to make (a heat/bulb load, some cooling fans and a cutoff).

I had a friend make up this beast, which works superbly, but seems overkill, previously I used ';the light bulb bowl of doom';.

[PaulJC]

I did order in a handful (less than £1ea from china) of 100w resistors so i could solder together a discharger but as of yet i';ve not got round to it...

[PropsToYou]

Out of curiosity, is there anything wrong with using the discharge feature on the charger?

[PaulJC]

Out of curiosity, is there anything wrong with using the discharge feature on the charger?

Nothing at all, just that it is slow...

I actually have mine running a discharge cycle now, 6S10000mah Packs and the best my charger (iCharger 306B) can do is 3.1A...

So to drain these packs to half (10000x3=30000, 30000/2 = 15000, 15000/3.1=4.8) will take nearly 5 hours **Changes mind and stops charger**

[PropsToYou]

Nothing at all, just that it is slow...

I actually have mine running a discharge cycle now, 6S10000mah Packs and the best my charger (iCharger 306B) can do is 3.1A...

So to drain these packs to half (10000x3=30000, 30000/2 = 15000, 15000/3.1=4.8) will take nearly 5 hours **Changes mind and stops charger**

Ah fair enough. Just wanted to check they weren';t renowned for causing issues.
Just saw your avatar, nice looking quad. Have you got a bigger pic of it?

[PaulJC]

Just saw your avatar, nice looking quad. Have you got a bigger pic of it?

Loads of pics and vids etc - HERE

[guest325]

Best way I have found to discharge a battery is to get a big motor and prop and just run them long enough to get the desired effect,  simples!!!

[Paul01]

I think the best way to discharge them is in your quad  ::)

[PropsToYou]

I think the best way to discharge them is in your quad  ::)

Hear hear!

[guest325]

True, but sometimes it just don';t happen  :-(