Question about lipos ?????????
 

Hi all i got a questoin abuot lipos i have been running my venom 5000 mah and i thought that maybe the capacities are going down but i think that the charger is not working right or poss balance wires could be causing it not to work and charge properly i ran one of the venom 5000 mah sun and it ran for a total or 11-12 mins total until the cut off kicked in by the way i have a GTB novak and 10.5 motor what are the chances the battery is not getting charged properly and thats what is causing the battery to not last or possible the battery balance wires acting up and not letting battery to charge right...... i was watching my charger bit again and it was charging at 5 amps and it was showing 8.39 on voltage and when i go to the each cell it was showing 4.07 and 4.09 i know my math is bad but i know that dont add up LOL can some tell me what i could be doing wrong or do i have a problem thnx Will G

Since you can charge a lipo with no balance wires hooked up at all, I doubt its anything to do with the balance wires. Try charging without balance wires connected and see if theres a difference.

How many runs does your lipo have on it? How old is it? Does your charger work on other batts?

i know that one battery is only like 6 months old and the other was bought used so unknown i was charging batterys on nihm also and it seemed to charge them but im not 1000 % sure they were taking full charge because i run the down and it would charge about 2200 mah in a 3300 mah battery or is that about right ..... im going to drain one of nimh batterys all the way and try charging and see what it does on that thnx

OK, with one only 6months old and the other used, I wouldn't think it was the lipo beginning to fade with age. It could be with the used one, but the other I wouldn't expect it.

2200 from a 3300mah doesn't sound bad, but depends on how long you ran it and how old they are. I've got a set of old 4000mahs and when I run them until the rc won't move anymore they take only 2100mah.

is it possible my cut off on my GTB is acting up because i know when it cuts off i start my charger up and it over 7 volts lately ??? lipo cut off should be around what 6.30 or something like that

i just ran my 3300mah nimh down to pretty much dead and it took 3000 mah so i imagine not the charger..... my guess is those batterys just went south:flaming: but owe well maybe cheaps cells or something not sure so it drains batterys too fast and my cut off kicks in even though maybe still somewhat still has a decent charge on it

I noticed the same thing you are seeing after buying a hyperion. My zippy, venom, and other batteries wouldn't take nearly as much as the hyperion. I noticed b/c the hyperion was brand new and the others are several months old. I'm interested to see if the hyperion looses its capacity as much as the others over a few months as well.

By the time you get the lipos out, they will have recovered some of teh voltage, so I doubt there is anythiung wrong with your GTB. Lipos voltage recovery is not a quick as NiMH, but lipo recovers just like NiMH. You'd have to have an onboard data recorder to see what the voltage was doing a the instant the lvc was activated.

Venom NiMh has a poor rep, some are good and some are terrible; it all seem to be tied up in how fresh they are. Lipo to some extent is teh same way. The newer generation (with teh 2C-5C charger rates) are better, but the older lipos seem to have about a 2yr useage life span. They start to go downhill after 2yrs whether they've been used or not. That and the expectation Venom has contracted for lower quality lipo cells to start with may be what you're seeing happen.

It sure doesn't sound like its your charger.

it sounds like something is set wrong on the charger, or it is faulting due to a battery problem, during chargin the battery will normally hit 8.4 and sit there while the charger finishes pumping mahs into it. (Not excactly like that but hope its sorta the explination you where looking for.)

Check your setting menu on your charger and see if it has a MAX mah input.

i had moved max mah input to 5400 due to another battery i charged for a friend ..... it just seems as though batterys are just falling off they have gotten worse with run time my thoughts are they are just dying off and i need new ones

then it sound like you said, time for some newer batts. I can PM you some info if you like.

What excactly do you need in terms of a Battery, is 5000mah 2s 20c ok?

Please send some info

i just put one of my receiver batteries on the charger and its still charging and holding at 8.40 and mahs are climbing still so 99 % sure batterys no good lol geez thnx to all that helped me

Never said which charger you're using, but a lot of chargers will be a few tenths or hundredths of a volt off - its calibration or just the accuracy of the device. What is important is that its not going the other way and overcharging them. My Accucel-6 has a calibration procedure to get it a little closer, but .04v was close enough for me.

My Hyperion charger agrees with my DVM, but it cost a lot more money and I'd expect it to be more precise with voltage.

As fas as new lipos, don't take the chance with Venoms, you never know with their stuff how old it is before you buy it. There are several good brands out there.

its the venom pro charger not the new one the older one its about .10 off