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Old 10-02-2012
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sosidge sosidge is offline
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Join Date: Jun 2006
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It's not difficult - in many ways they are easier to care for than the old round cells.

DO use a LiPo charger - I'm sure you will find many recommendations, I use Hyperion, but if you have a trusted local shop it might be worth buying something from them in case you need help in person. Don't use a NiCd/NiMH mode by mistake.

DO charge at 1C - this is the capacity rate, so for a 5000mAh pack it would be 5A. Some packs might advertise a higher charge rate but there really isn't any point.

DO use the balance leads every time - this will ensure that none of the individual cells in the pack get overcharged - it is such a quick job to plug them in it's crazy not to.

DO have a LiPo sack to hand - admittedly I don't usually use one but it is more peace of mind and some races will insist on it.

Also...

DON'T Discharge the pack below 3V per cell (6V for a 7.4V/2s pack). It will permanently damage them. Use the Low voltage cutoff in your ESC or buy a seperate cut-off or alarm for the car.

DON'T Cycle the pack unnecessarily. They don't need it.

DON'T Store the packs either fully discharged or fully charged. This can also damage them. I tend to just leave the pack alone after my last race of the day, for more peace of mind you can use the "store" mode that most decent chargers have.

And a little bit of LiPo jargon...

s means the number of cells in series - at 3.7V per cell - most 1/10th cars are running 2s/7.4V packs.

p means the number of cells parallel connected with each other - it's not usually published for car packs, but they are often 2s1p (just 2 cells connected in series) or 2s2p (2 sets of 2 cells connected in parallel, then connected in series).

4.2V The maximum voltage of a charged cell - so a 2s car pack will be fully charged at 8.4V.

CC/CV The way the chargers work. They start of with a constant current to bring the cells up to their maximum voltage, then maintain that voltage by slowly ramping down the charge current to nothing.

I think that covers most things!

LiPos are great. One of the best things to happen to the hobby. Basically, as long as you don't treat them like a d*ckhead, they will cause you no problems. Same for everything really!
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