Lipo questions....

[edgarcia59]

I recently bought a tenergy balance charger and 11.1v lipo from evike and I had a few questions.

Its a pretty nice charger but Im a little afraid to use it for fear of screwing up my new battery.

So here are my concerns...

1. How long should I charge my lipo for?
2. does the charger work like a traditional smart charger where it tells you that its charged?

[axisofoil]

A lipo charger will only charge your battery as far as it needs to go.

Use the "balance" feature, and all the cells will be charged to their maximum safe voltage.

[edgarcia59]

A lipo charger will only charge your battery as far as it needs to go.

Use the "balance" feature, and all the cells will be charged to their maximum safe voltage.

how long does it usually take to charge them?

[irishmaster]

my lipo charger beeps loudly when its done.  mine only takes 20 min. or so to charge.

[axisofoil]

A lipo charger will only charge your battery as far as it needs to go.

Use the "balance" feature, and all the cells will be charged to their maximum safe voltage.

how long does it usually take to charge them?

depends on how much you drain them, and how long you want them to last.

If you have drained like, 2% of their working capacity, it's going to take about 3 or 4 minutes to charge.

If you drain like 90% of their working capacity, it will take at least an hour to charge safely, depending on the quality of the battery and consistency of the charger.

I charge all of my batteries at a 0.5C rate, even though they are all rated to a 1C or 2C charge rate. FYI, 1C=1 Hour/Charge Capacity, 2C=0.5 Hour/Charge Capacity, and 0.5C=2 Hour/Charge. Most Lipo cells are rated to safely be charged at a 1C charge rate for their effective life span (anywhere between 100 and several thousand charge cycles, depending on cell quality, charger quality, use rates, usage methods and how well they're treated overall).

A "trickle" charge for lipo cells is 0.05C-0.1C, or approximately 10-20 hours for a full charge from a full drain. Very few lipo chargers offer this as a standard charge method, but is ideal for charging the batteries to maximize charging cycles.

[morugatu]

I'm not seeing the charger on evike you're talking about? So I'm going to assume its one of the more basic ones.

For the amount of amps to charge it at, charge it at the battery's full capacity or lower. I.E. 1500mAh battery charge it at 1.5amps or lower.

Full charge will be one hour, less than that if its not close to empty. I highly recommend investing in a good quality lipo smart charger as they can typically charge not only lipos but any form of battery. They also usually offer 'store' mode for lipos for when you store them (I highly recommend storing them in a cold place like a refrigerator) and 'condition' cycles for NiCD/NiMH batteries.

Investing 100 bucks in a computer smart balancer charger that takes all the thought and worry of any of my batteries and can run off car batteries was a life saver. I charge my whole team's lipo's and don't really see the point of trickle charging which is more effective for preserving NiMHs than lipo's. As long as you don't overcharge or over discharge your lipo's rated discharge rate, balance them, and store them in a cool (preferably cold) place, you'll be fine.

But to each their own.  

P.S. Not to thread-jack, but does anybody know if battery plus will repair lipo packs? One of the balancer connector cords popped off a cell and I'm not comfortable soldering it back on myself.

[XavierMace]

Depends on the store/tech.  Most won't.  I've been trying to find someone to reconfigure a couple of packs for me with no luck.  Most people don't want to touch them.

[axisofoil]

I've successfully soldered/reconfigured my fair share of LiPo batteries.

It's really not that hard. Just like any other battery, but with an extra wire going to every cell for the balance tap

[ThatGuy]

A low voltage alarm is a good thing to have also. You don't want to run the lipo dead it will damage the cells. Look up lipo fire on YouTube lol good entertainment. Good luck!

[axisofoil]

A low voltage alarm is a good thing to have also. You don't want to run the lipo dead it will damage the cells. Look up lipo fire on YouTube lol good entertainment. Good luck!

Or just get a computerized mosfet that won't let you overdischarge.

I like extreme fire mosfets.

[jdmsquadleader]

couple things on lipo's and chargers are
1 they are sometimes tempermental
2 if discharged to far they are not safe to recharge
3 if not balenced the life of the battery is reduced by a ton
4 if u pull too much power from them like pass there c rating they will heat up and fail and sometimes catch on fire
5 if improperly charged they can blow up/catch on fire
6 if charged to long they can also blow up/catch on fire


some ways to prevent these things are
1 buy a smart charger which will shut itself off when the battery is charged
2 check the battery every 10 mins in case of a fail charge
3 buy a balancer if ur battery charger does not come with one
4 figure out a way to know when ur battery is close to being discharged
5 buy a lipo bag or metal ammo box to charge the battery in so if it does catch on fire or blow up u can prevent the stuff from spreading
6 never charge the battery if the cells swell or are puffy
7 make sure u have the right charger nimh chargers and nicd chargers will not charge lipo batterys
8 make sure u have the proper c rating so u dont blow ur battery i believe 20c-40c is where u want to be at
9 dont puncture ur battery
10 read the damn instructions if not 20% of the time ull prob end up messing up ur battery/charger or somtin else

if u have any questions pm me

i used to work at a hobby shop in socal that dealt with lipo's for planes cars heli's boats which i used for airsoft before the airsoft companies started marketing them to the airsoft users  


if anyone feels i have missed somtin or i am wrong about somtin pls correct me

[axisofoil]

3 if not balenced the life of the battery is reduced by a ton
It's not so much that the life is reduced as far as charging cycles are concerned, more that you are much, much, much more likely to overdischarge or overcharge one of the cells of the battery without overcharging the pack as a whole... leading to some major issues.


some ways to prevent these things are
7 make sure u have the right charger ]nimh chargers and nicd chargers will not charge lipo batterys
They WILL charge them. Just not safely. This is one of the easiest ways to create an explosive situation.

8 make sure u have the proper c rating so u dont blow ur battery i believe 20c-40c is where u want to be at
This is talking about the pack's DISCHARGE RATE. Not the CHARGE rate. For clarity. If you charge your lipo at 20c or 40c, I GUARANTEE you that it will blow up within three charges. You want to charge at a MAX of 1c, maybe 2c if you know your packs are designed for it.

It's not the c rate that you should be interested in, specifically, when looking for discharge rates. You want a continuous discharge of at least 25amp, and peak discharge of at least 40 amp. To get these, multiply the pack's C rating by the mAh of the pack, then divide by 1000.   For example, a 1500mAh lipo with a 20C continuous rating is rated for 30 amps continuous output, while a 5000mAh lipo can be rated at just 7C continuous and would therefore be rated for 35 Amps continuous output.


if anyone feels i have missed somtin or i am wrong about somtin pls correct me
Done.