Is it okay to take the LiPo off the charger @ 95%?
 

Is it okay to cut the charge short on a LiPo? Say I'm at the races, the next heat is in 2 min and I need the battery. It's charged to 95% or somewhere UNDER 100. Is it okay to disconnect and run? Is it going to harm the battery?

Also, my Hyperion only has 100mah increments. My battery, however, is 4350mah. Is it okay to not charge that extra 50mah or is it crucial?

There should be no problem with partial charging lipos. I regularly charge to only 90%-95% a pair of Trakpower bricks with no problems.

The mah setting on the hyperion charger will only effect the current rate that the pack is charged at. I have a couple of the evolite packs that I charge at 50mah over which causes no problems either. Either way you will get a full charge unless you end it early.

with the hyperion chargers, in the owners manual it says to charge the 4350 mah packs (for example) at 4400mah. it will not harm the battery. i personally love my eos1210i.

Awesome, that's what I'm using, the 1210i. I must have missed that part when I read the two page manual, haha.

Thanks.

no problem.

Nicad batteries are notorious for retaining a memory (mAh degradation) due to partial charging/discharging but Lithium batteries do not have these issues. Partial charges or discharges have no ill affects to Lithium batteries.

Can even be a good thing. Reducing the cycle depth of lipos can increase their cycle life...

^ Yup. I set my CC/CV threshold to 4.10-4.15v/cell to help increase their life cycle, and you don't lose much runtime (at least not noticeably).

Right ON!!!

Awesome, I'll make sure to keep all this in mind when racing tomorrow. Thanks again guys.

FMA actually said to charge the Scorpion packs to 90%. I love my Scorpion packs. Too bad they were too expensive.

Dosn't most of the cell balancing happen during the last few percent of the charge?

Depends on how matched the cells are and if they have an imbalance even before you start charging. To make sure the cells have time to equalize before the end of the CC charge cycle, I balance off-line. Once they are balanced (or very close), I then charge and balance at the same time.

Ah, balance then charge, rather than charge then balance, basically. That sounds like a nice technique.

Balancing should be done while charging. If it's done before, there's no garantee the cells will remain in balance throughout the charge...

I remember when Lihium Polymers didn't come with a balancer. I actually had a few. I even had the Highest capacity single cell lipo. I still don't balance most of my packs. I only use a balancer on my 5S TP packs. I balance them before and during the charging. BTW here is a picture of that highest cpacity cell and pack: http://www.rcpics.net/view_single.php?medid=80310, http://www.rcpics.net/view_single.php?medid=80309 and http://www.rcpics.net/view_single.php?medid=80308. The M18 is just to show the size of the pack and cell.

He (BrianG) did say that he "then charges and balances at the same time" after doing a preemptive balancing.

Just watch out when balancing a discharged pack as you could possibly discharge one cell below 3v. Most balancers will not allow this but I always charge when I balance, even if it is at a low rate like .3 amps.

Wow, what c rate was that lipo? 1c, or 2c!!!!

Those tiny wires coming of the cells to that little pcb, does not look like thick enough wires to warrant the use of a deans plug. I am glad battery technology has improved!

The cells are 10C and I tried it out in my Stampede. Ran the darn thing for over an hour, not continous, but I timed every run. I stoped using them because I coudln't find a suitible charger at the time. Both packs were dead after I got my Astro Flight. I don't know why the PCB is there, but the factory at the time told me it was to protect the cells from over discharge. I did take the PCB out of the other pack, but a few days after I did the pack had a short. It looked just like lightning and one cell went bad.

He did. So, safer to balance during and after, but it depends how good the cells and /or charger are. Why cant life just be simple.....:tongue:

Sucks that they died, looks like a much larger version of maxamps 10000 cell. That cell is more like an 8c IMO. The 4s 10000 pack got hot in my buggy (7xl, geared for 40mph). Too heavy for my liking, would be good for a lower drain app like a starter box (blasphemy!)