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I have just purchased these shorty packs and am looking to buy more if I like the way these batts work.

I have always run a lipo cut off with all of my Lipo's which drops out at 6.0v on 2cells. I always recharge and balance after use leaving them stored full.

Is this still the best way to maintain these cells in todays day and age? Any suggestions?
Cheers-Jason.

To be honest storing fully charged is bad news for some lipos. They can end up swelling, especially if stored full for a longer period of time.

I store mine at 60% charge, roughly 3.8v (per cell), and have no issues.

Paul.

Thanks Paul. I have heard of and been thinking of charging (storing) with less than a full charge.
60% sounds good to me.
Thank you- Jason

you're going to love those batteries, so much punch.

one thing i do with all lipos is never charge at more then 1c, even if the battery label says it can be charged at 5c.
i also top them off after each heat/race. this puts the least amount of stress on the battery and increases/conserves it's life span.

In saying that I've found that if you only ever run the pack half flat and charge it up they go doughy and loose punch. Lipo's technically don't have a memory but my experience has been that they do show some form. A discharge to cut off and a full charge seems to fix it.

So in saying that I think lipo's do need to be discharged to a cut off every now and then to keep them in top performance.

Check your charger instructions to see if it has a storage charge mode. Most lipo chargers do. I also agree with the 1c charge rate. I never charge any of my batteries above 1c.

Was thinking of a couple of those packs myself. Can you compare them an anyway to the regular sized long packs?

From personal experience, every shorty lipo I stored fully charged has puffed. About 30% of the full size packs stored fully charged have puffed. I have moved to almost all shorty lipos now, my charger has a storage/balance mode and it puts them at 7.6 volts, which matches the 3.8 volts per cell already mentioned. I have 3 shorties now, they have all outlasted the others that died a swollen death.

I love the shorty lipo in the gold pan, pushed as far forward as the servo allows simply awesome.

I haven't been using LiPo's all that long, but I've had success not letting any of my 2S or 3S packs(Trakpower & Venom) reach the ESC's cutoff and charging them to 3.85V per cell before storage since that's what I've read on the Interwebs. I also charge them at 1C and always balance them during every charge.

A friend of mine with a few crawlers usually never balances his generic 2S hardpacks, almost always runs them to the cutoff and submerges them in water/mud all the time. He hasn't had any trouble with puffing, dead cells or lower run times.

I always run mine until the lvc kicks in. Are you not supposed to do that? I thought that was the whole point of having lvc!?

I'm going to chime in a littlle bit here.

I store my lipo's at storage voltage, AND I store them in the fridge in the crisper drawer.

You don't want to freeze your lipo's, but the closer you can get them to 33 degrees, the longer they will last. Lipo cells degrade over time. Keeping them cool and at storage voltage is the best way to slow that process down. The typical crisper drawer temp is 35 degrees.

Heat and/or storage @ full charge will shorten you lipo's lifespan.

I like to run my lipo's down to LVC, but.... I typically set it on the high side, around 3.5v per cell.

If you should accidentally over discharge a lipo......and your charger won't charge it because the voltage is too low.....
Disclaimer, do at your own risk...if the lipo looks unsafe (excesivly puffed) I'd dispose of it.
But anyway.....putting your charger into "nimh" mode will let you charge an over-discharged lipo back up into the range where you can charge it as a lipo.

I did this for my Father-in-law. He had a fairly new battery that was over-discharged. After 10 minutes of charging (@1C) in nimh mode it brought it up to over 3v per cell and he was able to charge it normally.

I'm leary to charge a lipo at 1c in NiMh mode. Technically it probably wont hurt the battery as it's still a linear charge, but I've always found a minute or two @.5A does the trick. It has worked well to revive batteries run down to 1.47v cell.

For batteries severely out of balance you can also make adaptors to charge the cells in the pack seperately through the balance lead.

Of course this is not recommended practice but it does work if you know what your doing.

I've never heard of the individual charging, but that does make sense. I have heard of charging 2 lipo's at once though (in parellel).

Probably safer to save an under-voltage lipo like that (0.5C), but I figure if it's "that" low, it's not really going to care.

Do you refridgerate yours?

andymac0035 wrote: He had a fairly new battery that was over-discharged. After 10 minutes of charging (@1C) in nimh mode it brought it up to over 3v per cell and he was able to charge it normally.

had quite a few of these locally do this and as I have done the same thing. Issue here is the battery is never the same afterwards. I don't know all the chemical makeups of these things but an overly discharged lipo usually means faster dump times, longer future charge times, balance issues, etc. Seems they behave rather erratically. You wouldn't believe how many lipos come back to the LHS too low of voltage wanting $ back after a week or so of use. Most of these don't have low voltage cut off ESC or show up with the battery plugged in since the last time they used it .

I've heard of the refrigeration technique but don't use it personally. I do know that when I used to bring them to work and sit in a very hot car it would mess with charges. Be fully charged night before and next night they would be close to dead after sitting in a very hot car. Puffed a few like that also .
-new gensace battery...$33
-having to drive past the LHS 10 miles to get my stuff & then back to run...extra time and gas of approx $5
-having to drive to get something to eat because you missed the food order cutoff time (& discount)...$10__________________________________________________________________
-not burning down your r/c cars, '02 ford explorer, and possibly an entire parking lot of co-workers cars & trucks...priceless

I also personally run almost all my batterys to the LVC and haven't had any issues doing so. Not running to LVC makes sense to me with having that extra care of 'not getting too close to the edge'. When I actually would race they never reached that point anyway.

After all this its really up to how you want to take care of things. These are still 'wear out' items. There will be problems if you try to 'cheat' a battery so expect it. Its all 'disposeable' income. I've always been told if you can't afford to do something then don't eat so you have extra $ to do it .

disclaimer: the previous is just my opinion from my experience. Not telling you what to do or how to do it...just what has worked for me.



Todd