Uneven Cells

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.
Crash

Crash

Well-Known Member
Messages
3,693
Location
Chicago
I have a 2 cell LiPo that has one cell over a 1 volt lower then other
 
Dan, please post the voltage numbers.

also, where in the charge process are these voltages from? Did you just finish a charge cycle?

Does your charger have a balance mode only?
 
I have never seen that much difference the most difference I've had is .4 Did you balance it and is the LiPo ok?
 
i NOTICED THE voltage difference after a run.

2.82 4.20 after balancing
 
Crash said:
i NOTICED THE voltage difference after a run.

2.82 4.20 after balancing
Click to expand...

aight, that is messed.

did you notice the same amount of power when you ran the truck because that one cell didnt have any drain. might even be suspect that the bar came loose and isnt even connected inside the pack anymore.

did you have a crash or anything during the run? (no pun intended)
 
I crash almost every time I run so, not sure.

the voltage posted is after I treid to balance the pack.

I didnt write down the ending voltage after the run when it happen.

I did notice the votage on 1 cell was below 3

and didnt balance out during charge
 
do you know anyone close by with a LiPo charger? maybe your lhs?

you could rule out a charger issue with another charger. i have an easier time believing the 8.4v caz if that cell is truely at 2.82v, it should have at least puffed the cell if not worse.
 
I wouldnt think its the charger, no issues with 2nd pack voltage readings

maybe its the balancing leads from battery
 
is that the pack you had to re solder them on?

and do you have a multi-meter?
 
its not the pack I repaired

I did put a voltage reader on pack, its 8.2 volts now
 
are you plugged into the right port on the board ? I put a 2s into the 3 s port and got wild readings like this once .. I almost poop myself
 
@ Justin~ ya, the 2s have their own spot the 3s are different size so its dummy proof



I measured both packs this am with voltage meter after balancing both, they are .01 difference in total voltage. I think the balance lead from battery is messing up the reading on one cell when its read by charger.

I will put them threw a run today and see if it puffs up on me.









:castle:
 
Last edited by a moderator:
GL bud ... I was hoping it was the lead! I'm having issues with a Maxamp cell myself. just not this bad
 
I would solder on new balace plug and re shink wrap the pack. But if they are Maxamp make them stand behind it and replace it. I won't touch maxamp stuff with a ten foot pole. By all accounts and my own experance they are worse than the $12 rhino packs from hong kong.
 
I have been monitoring packs, they are exactly the same when reading the voltage with the volt meter and the total voltage on charger. so, I'm thinking the balance lead is corrupted in some way.

I'm not going to mess with it for now.

thanks for da help


















:joker:
 
Be careful because if the cells are out of balance you are over charging one cell and over discharging the other.
 
The Pope NJ said:
I would solder on new balace plug and re shink wrap the pack. But if they are Maxamp make them stand behind it and replace it. I won't touch maxamp stuff with a ten foot pole. By all accounts and my own experance they are worse than the $12 rhino packs from hong kong.
Click to expand...


I would have disputed this comment before you became a NL Chapter president, but now i may just sell my maxamp packs and buy some of these rhino's, can you give me a link?
 
Have you verified the individual cell voltages at the balance plug with a different meter? If you're just going by what the charger says, it might be wrong. If one meter is saying the the total is 8.2, and the monitor is giving you individual readings that don't add up to that, then one of them is wrong. I'd check it with another meter and make sure. For preference, a standard multimeter would be best so you know it's the same circuit measuring each cell.

frddyj said:
I would have disputed this comment before you became a NL Chapter president, but now i may just sell my maxamp packs and buy some of these rhino's, can you give me a link?
Click to expand...
Hobby King is the best place to get good, cheap lipos. They sell Rhino, Turnigy and Zippy, which I suspect are all the same batteries with different stickers on the shrink-wrap. They're unbelievably cheap, especially when compared to "boutique" vendors like maxamps. I have four batteries from them, and they've all performed perfectly. Shipping is expensive, but when the batteries are literally 1/4 the price of US vendors, it's still a good deal. Try finding a 2s 5000mAh hardcase anywhere else for $23. I dare you.
 
candre23 said:
Have you verified the individual cell voltages at the balance plug with a different meter? If you're just going by what the charger says, it might be wrong. If one meter is saying the the total is 8.2, and the monitor is giving you individual readings that don't add up to that, then one of them is wrong. I'd check it with another meter and make sure. For preference, a standard multimeter would be best so you know it's the same circuit measuring each cell.


Hobby King is the best place to get good, cheap lipos. They sell Rhino, Turnigy and Zippy, which I suspect are all the same batteries with different stickers on the shrink-wrap. They're unbelievably cheap, especially when compared to "boutique" vendors like maxamps. I have four batteries from them, and they've all performed perfectly. Shipping is expensive, but when the batteries are literally 1/4 the price of US vendors, it's still a good deal. Try finding a 2s 5000mAh hardcase anywhere else for $23. I dare you.
Click to expand...


Thanks

I'm not sure how to measure the individual cells threw the balance lead.

I am testing the total voltage threw the deans and that matches the charger readings
 
On the balance plug, the black wire is common and each of the other wires are positive for one of the cells. So if you have black, yellow and white, you measure black to yellow for one cell and black to white for the other.
 
candre23 said:
Hobby King is the best place to get good, cheap lipos. They sell Rhino, Turnigy and Zippy, which I suspect are all the same batteries with different stickers on the shrink-wrap. They're unbelievably cheap, especially when compared to "boutique" vendors like maxamps. I have four batteries from them, and they've all performed perfectly. Shipping is expensive, but when the batteries are literally 1/4 the price of US vendors, it's still a good deal. Try finding a 2s 5000mAh hardcase anywhere else for $23. I dare you.
Click to expand...
lol that was a joke ... put those cells behind a 150-200 amp system and its all different story's with the same end result.

Reads like this:
"I didnt so anything wrong, but" My flux caught on fire... I called hpi and they laughed at me and told me I voided my warranty using these battery's , why?

You can get away with them running 17.5 light stuff low load... Put them in a savage and none of us will feel for you when you burn it up. I pay hundreds for my lipos and don't mind paying for the fire prevention...
 
No battery pack will ever cause your ESC to catch fire, no matter how bad it is. Bad packs can give poor performance or destroy themselves, but they can't hurt the ESC unless they actually explode and physically damage it that way. If your ESC melts down, it is because it is overworked, shorted on the output side (the wiring or inside the motor itself), or was defective from the factory. You can't blame a blown ESC on the batteries.

And honestly, I've never seen any legitimate testing done that shows the HK batteries to be all that much different than the premium brands. The only thing close to a scientific test I've seen was the big squid LiPo shootout, which puts zippy smack in the middle of the pack. And honestly, the packs that beat it didn't beat it by much in any of the categories. The number one pack (hyperion) was a whopping 2mph faster and actually had a lower measured capacity - all for more than 3x the price.

I know that RC is a competitive thing, and that it's worth it to a lot of people to pay 3-5x more for a battery that is maybe 5% better. It's your money and your truck, so if that's how you want to run, then awesome. But it is a mistake to automatically assume that a cheap pack is "vastly inferior" to an expensive one, because what little verifiable data exists (and my own experience with them) says they're damn near as good.
 
so I tried to check the cells individually threw the balance leads but that didnt work

one reads 4.2 and one reads 8.4 so thats not going to work.




I did go ahead and replace balance lead and plug.........Its fixed!!!!!!

Thanks to all that helped~




drummerguy
 
candre23 said:
No battery pack will ever cause your ESC to catch fire, no matter how bad it is. Bad packs can give poor performance or destroy themselves, but they can't hurt the ESC unless they actually explode and physically damage it that way. If your ESC melts down, it is because it is overworked, shorted on the output side (the wiring or inside the motor itself), or was defective from the factory. You can't blame a blown ESC on the batteries.

And honestly, I've never seen any legitimate testing done that shows the HK batteries to be all that much different than the premium brands. The only thing close to a scientific test I've seen was the big squid LiPo shootout, which puts zippy smack in the middle of the pack. And honestly, the packs that beat it didn't beat it by much in any of the categories. The number one pack (hyperion) was a whopping 2mph faster and actually had a lower measured capacity - all for more than 3x the price.

I know that RC is a competitive thing, and that it's worth it to a lot of people to pay 3-5x more for a battery that is maybe 5% better. It's your money and your truck, so if that's how you want to run, then awesome. But it is a mistake to automatically assume that a cheap pack is "vastly inferior" to an expensive one, because what little verifiable data exists (and my own experience with them) says they're damn near as good.
Click to expand...
You need to call castle and let them tell you ... I wont try and educate you on sine waves and all the other things that effect the ESC in 8th scale systems. I have made that call. Do it, its worth your time... If they are properly rated any pack will be fine. The issue with the sub par brands is they are rated at 30 C yet put out 22-25 and void your warranty on the castle system with HPI. I think its 26C or so might be 24 that is the cut off , not sure but any pack less then that WILL smoke the MMM. Only reason I use the Hyperion packs Is I run 5S I need my pack ratings to be exact on the 2S and 3S. The other company's can't give this to you. Ill gladly pay. On my 10th scale stuff Ill run anything and do ..

Crash said:
Thanks

I'm not sure how to measure the individual cells threw the balance lead.

I am testing the total voltage threw the deans and that matches the charger readings
Click to expand...

Awesome crash !
 
Last edited by a moderator:
Crash said:
so I tried to check the cells individually threw the balance leads but that didnt work

one reads 4.2 and one reads 8.4 so thats not going to work.




I did go ahead and replace balance lead and plug.........Its fixed!!!!!!

Thanks to all that helped~




drummerguy
Click to expand...




they seem to be fixed, burned threw the packs two more times.
The numbers are perfect now.

only 44 more days until 6S




:FarleyParty:
 
update:

the packs are perfect, discharging within .01 of each other

the charge and balance time was within 7 seconds of each other on last charge........
 
You must log in or register to reply here.

Latest posts

Members online

Total: 161 (members: 1, guests: 160)
Back
Top