does charging lipo's at low amp decrease punch?

[blueb8llz]

i heard that if you had a 3300 mah nimh and charged it at less than 3.3 amps, you get more run time but less punch in your batteries.
is this the same way for lipos? what if i had a 5k lipo but charged it pretending if it was only a 1k lipo, and just charged it 5 times...will it be less punchy?

[squeeforever]

Originally Posted by blueb8llz

i heard that if you had a 3300 mah nimh and charged it at less than 3.3 amps, you get more run time but less punch in your batteries.
is this the same way for lipos? what if i had a 5k lipo but charged it pretending if it was only a 1k lipo, and just charged it 5 times...will it be less punchy?

Well you wouldn't charge it 5 times, you would just charge it for 5 hours, but to answer your question, I don't think it will make a difference like with NiMH. That only really works when there fresh off the charger anyway (NiMHs that is).

[whitrzac]

Originally Posted by squeeforever

Well you wouldn't charge it 5 times, you would just charge it for 5 hours, but to answer your question, I don't think it will make a difference like with NiMH. That only really works when there fresh off the charger anyway (NiMHs that is).

most chargers have a built in "safty timer" that prevents you from charging it that long...

[squeeforever]

Originally Posted by whitrzac

most chargers have a built in "safty timer" that prevents you from charging it that long...

True.

[BrianG]

Can't the safety timer be changed? I know that charging at smaller amps isn't doing much to help the battery, but some chargers have a low power limit and NEED longer charge times to compensate.

[lincpimp]

As for the initial question, I do not think a slow charge will do anything for performance. As long as the pack is in balance and all of the cells are matched well you should be fine. If your pack goes out of balance (as the cheaper packs will) a slower charge can give the balancer more time to do its job during the charge. This depends if you have a charger with a built in balancer or use a stand alone charge thru balancer. Or you may have a non charge thru balancer (like a blinky).

All said and done I do not think a slow charge will benefit the lipo at all.

[blueb8llz]

ok cool . thats all i needed to know. cus my zippys need to be slow charged to give it time to balance all 3 cells.
what about if after everytime i use the zippys, they are all unbalanced again. Does this mean the zippys have a lost in performance? i bought these zippys used, so i have no clue how they performed when they were brand new.
my guess would be they were alot more punchy and gave more runtime as im only getting like 20 mins with a 2200mah 3s for my rc18mt.
im trying to figure out if i need a new lipo or not. ill definetly get one if im losing performance with these unbalanced packs.

[93firebird]

This is a very good question that I was wondering also, I purchased a 4s pack at 4000mah and I'm having a hard time finding a charge through balancer that will handle more then 3 amps for a reasonable price (not over 50). So I should be fine charging at less amps it will only take a little longer, Is that the answer?

[lincpimp]

Originally Posted by 93firebird

This is a very good question that I was wondering also, I purchased a 4s pack at 4000mah and I'm having a hard time finding a charge through balancer that will handle more then 3 amps for a reasonable price (not over 50). So I should be fine charging at less amps it will only take a little longer, Is that the answer?

Get a hyperion lba10. They can be had for 40 bucks from most places. I know BPP has them.

[BrianG]

You generally don't want t6 charge at much higher than 2A through the balance leads as they are too small and will develop voltage drop across them making the charger's reading inaccurate. The best solution is to use a charger than charges through the main leads (which are designed for higher currents) and use a balancer to bleed off excess charge on high cells.

[blueb8llz]

back to my second question haha. does the unbalanced cells decrease power/punch in the performance of the lipos? i know off the charger, the cells are balanced, but after running the truck, all the cells are unbalanced again.

[redshift]

In my exp there is no loss of punch at a lower charge rate. Before i got my Duo2 I used a buddy's Polycharge 4 that had a 3 amp max rate, and I am getting the same punch out of my packs charging them at 6-8 amps now.

"all the cells are unbalanced again"

How much out of balance?

If it's a lot then one cell will always be working harder and will of course make the pack weaker overall... but if it's not much then probably no worries other than shortening the lifespan of the pack.

[blueb8llz]

after the run, my 3s lipos reads 3.90 4.11 4.01
i would say thats pretty bad haha. so you think i would see a power/punch increase if i was to purchase the EXACT same zippy lipos or will i just see an increase in run time?
one other thing, why are my zippys so unbalanced in the first place? is it because theyre cheap batteries, cus if thats the case, wouldnt brand new ones do the same thing?
or is it because those lipos are getting old? i bought them used with the truck.

[bdebde]

Low charge rates should not affect the punch. It is good for getting a way out of balance pack in line (balanced). As far as checking balance on a partially discharged pack; I know at least one manufacturer that says not to worry about balance at a partially discharged state. They say to only balance a fully charged pack since the packs are matched for max voltage and min voltage as well as capacity, but the voltage can vary quite a bit between the cells as they are being discharged. So, charge it up and then worry about balancing.

Yes, cheap packs may not be well balanced to begin with.

remember Zippy lipos are still chinese lipos they are cheap for a reason, but good bang for the buck....I prefer to use enerland cells I do have a Zippy 6s pack and it just doesnt have the punch my FPs do