pubmaster861

My second lipo I had in storage might be screwed. One of the cells dropped big time in storage and is stuck at 120 mv away from the other cells . Is it wrecked? I'm trying to charge it on my dynamite passport+ but it won't begin the charge until the unbalanced mv is lower battery toast or would a server ate balancer like a team check point balancer help?

nitrosportsandrunner

not sure what you mean by 120mv

if the lower cell is at least 2 volts then I would try charging it on nimh setting for a couple of minutes (watch it of course, dont leave it unattended) and then try to balance charge it again.
Im assuming your charger is thinking the lipo's voltage is too low. But under nimh setting you can pump some power into it and get each cell to at least 2.9v each.

pubmaster861

Mv milli volt, 3 cells are all around 3.8 and the 4th is like 3.4, and my charger will not start charging til it's balanced the mv to a smaller number,

yakfish

My Feedback: (27)

If they are only 0.4v apart then the battery is probably fine. you could try a alancer but it might be your charger that is the problem

nitrosportsandrunner

dang, your charger is picky. Mine would have no trouble balance charging a lipos with cells that had those numbers.

If you own a seperate balancer (I have a $20 blinky balancer) you could put it on that to balance the cells before charging.

pubmaster861

Ya I was thinking about one of those, is it actually called a blinky balancer? It be nice to balance them before they charged cause don't they charge faster not on the balance charge setting?

nitrosportsandrunner

I suppose the charger faster that way.
I have always balance charged my lipos on my thunder AC6 charger. It only takes 1 hour to charge a 2s 5000mah pack. Thats plenty quick enough for me. And since I have several 2s packs, I dont want to try and remember when each was last balance charged.

I use my blinky balancer mostly to check the voltage...so I dont grab a lipo thinking its a fully charged one, only to get to bashing and find it was drained.

mine looks like this one:

Maj_Overdrive

My Feedback: (11)

You can try charging it on the NiMh setting for a minute at 2amps, sometimes they'll even out a little bit. Some Lipos can get to be a bit of a pain to balance when they're that far out though. My Hyperion 610i (great charger) would charge and balance them being that far out or worse. But I did have a couple packs that were really stubborn and taking forever and they were half as far out as yours were. My solution was to buy a balance lead and charge the cell with the lowest voltage individually until it was closer to the rest of the pack. You'll want to charge at 2amps since the balancer wires are small and monitor the voltage to get it close to the rest of the pack. On the two packs I've done this to, both have maintained a more even balance since and charge up in 15-20min like normal. I'd suspect you'll have similar results, being off less than .5volts doesn't sound like a dead or overly weak cell.

For a Lipo pack, its recommended you always balance charge. Each cell should be charged to 4.2 volts max, going over is how you ruin cells, start fires, etc. Your 4 cell pack would be 16.8 volts fully charged with all cells at 4.2 volts. But if your one cell stayed .4 volts lower than the rest and you didn't balance charge, the results could be 4.0, 4.3, 4.4, 4.1 and final voltage is still 16.8 volts, That may not be the end of the world or start a fire, but its not the best thing for the pack. Balancing a pack before charging might speed up the process, but more than likely it won't. Cells discharge and take a charge at slightly different rates, 5 minutes into a charge they won't be balanced anymore if you're not balance charging.

pubmaster861

Ok cool thanks for the posts, but talkin about the finally voltages after charging . Mine are always different !!! Don't think I've ever had 4.2 across the board, and that's with either my 4 cell that I use in my truggy or the 2 and 3 cell I use in my mini revo, all my batteries are Turnigy. The 4 cells are the normal turnigys and my revo packs are nano techs, and they make that lil car rip with stock motor and esc !!!!! Overdrive are you telling me that your lipos balance perfect to 4.2 every charge?!?! This seems strange to me

Maj_Overdrive

My Feedback: (11)

I also run Turnigy's myself (not Nano's, regular 5s 5000mah) and a couple older Polyquest 5s 6000mah. The Polyquest used to balance out to a 4.18-4.20volt spread really easy, and wouldnt take long to get them totally even, usually 5min. Now that they're 4-5yrs old they take forever if I want a tighter spread than 4.15-4.20volts. The Turnigy's were like the Polyquest when new, but after the first season they're like the Poly's are now, 4.15-4.20 spread and takes forever to get them tighter. I think the charger can sense this or sees a pattern while charging the pack and signals the end of charge knowing it'll take forever to get better than a 4.15-4.20volt spread. When the batteries were newer it would get the voltage spread tighter or completely even before signaling the end of charge. Either way my Hyperion will keep balance charging, even after signalling end of charge, if I let it. So yes, I've seen a perfectly balanced pack, but only when the packs were new or pretty close to it. But theyre not bad now, its close enough for me either way and they all seem to discharge with about the same spread so I don't think it's hurting anything. We're only talking .05 of a volt anyway.

phmaximus

I would reccomend getting a Imax B6,for $20 a digital charger that can charge Nimh, Nicd, Lipo, Life & PB is wasome value, im running 2 B6's and one B5

Ive had heaps of batteries out of ballance and it fixed them up with no problems back to 4.2v/cell

I did have one new battery that it was struggling to ballance, so i discharged the pack to about 3.6v/cell and re ballanced it. now its sweet as.

If u have a stubborn battery it can even cycle the battery up to 3 times, great way for checking the batterys condition