New Battery Help Needed

[jondilly1974]

I also just found a setting for max mAh and the default is 5000. ??‍??‍??‍

 

[Notorious J]

I bought a Hitec LiPo Checker at the LHS today when I went to buy my Reaction 4S 5000mah 50C pack. How close should the cells be?

1) PH 3S 5200 50C 3.79-3.94-3.96
2) PH 3S 5200 50C 3.81-3.80-3.79
3) Ovonic 3S 7600 50C 4.21-4.19-4.22

I need to run the Ovonic down for storage real quick. Gonna test out this replacement spur that I just plopped in.

I was not aware that it did that. I will try that next charge. ??????

Edit: Ovonics is now showing 3.69-3.68-3.69 and lasted about 10 mins of hard driving down my street from a 4.2 charge.

Not that I'm a pro at this, but that first cel in the first PH battery might be cause for concern. If you balance charge it, and it takes forever without seeming to get there, it might be because that cell is going bad. I had the same thing happen recently with one of my 3s gensacearespammers, and decided to scrap it before something worse started to happen.

 

[jondilly1974]

Not that I'm a pro at this, but that first cel in the first PH battery might be cause for concern. If you balance charge it, and it takes forever without seeming to get there, it might be because that cell is going bad. I had the same thing happen recently with one of my 3s gensacearespammers, and decided to scrap it before something worse started to happen.

That was my concern as well. I will give her one last chance to get right, or else ???

 

[arrmadillo]

The cells should be close like #2 and 3.
#1 has a large gap from low to high. Maby if you keep on balance charging that pack it will come back into spec, something you should have been doing from the start.I

If LVC is coming on at 3.68 it's set high.

 

[Captain Dirt]

I also just found a setting for max mAh and the default is 5000. ??‍??‍??‍

You should set up your lipos individually on that charger, that way all you have to do is bring up the setting for whatever battery you're charging and presto. Otherwise, if it's set up for 5000mAh then your 7600mAh won't even charge all the way.

 

[jondilly1974]

I tried to use the discharge function on my charger to see if I could get all cells matched and only the first (low) cell dropped. When balance charging, only the second and third cells charge. I already got a refund for this battery, so I’m not too upset. I was told I can dispose of it, they don’t want it back. Is there a reasonably safe way to make it a 2S pack for my Granite 4x4 Mega?

 

[jondilly1974]

I think I may have revived it! I did a discharge as shown above, which looked really bad. Then for poops and giggles I ran a balance charge and this is the result. Fingers crossed ??

 

[olds97_lss]

I have a feeling once you put it under load, that same cell is going to drop out on you which will give you a premature LVC, or it could run so low that it dies painfully and takes your truck out with it. At most, I'd only run it a minute, then unplug and check the cell voltage to see where it is.

I've had a few packs die on me over the past couple of years and normally just one cell goes bad. Usually, if I charged them, then let the pack sit overnight, check the voltage in the morning, the bad cell would have dropped considerably. When that happens, you shouldn't use the pack anymore.

If your careful, you can disassemble the pack and make a 2S pack out of it. I've done that a few times, but it was to take 3 2S packs to make 2 3S packs. You need a high wattage iron though as the solder they use is high silver I think and there's a lot of it, so a 50W iron won't touch it. It will just make it hot. I bought a cheap 100W iron and it makes short work of them.

A 3S pack I made out of SMC 7200mah 2S packs:

That wasn't the end result, that was just after soldering. I put protective layers of tape under the wires so they wouldn't short out on anything and behind the battery tabs for support.

SMC uses 2S2P for the packs I had, which is 4 cells total, two in parallel, then 2 pairs in series. Was a bit of a pain dealing with that, but I made it work and have been using the "3S" packs I built for the past 6 months or so in my smaller trucks.

I used the plastic case halves to protect the top/bottom of the pack and just wrapped it with fiber tape really well.

To go from 3S to 2S, you would need to get some 2S charge plugs. Although, a 3S charge plug might work if you hook it up right. I just bought some spare 2S and 3S plugs for when I did this and in case I rip off a 2S plug when out bashing. They are cheap enough.

 

[jondilly1974]

I have a feeling once you put it under load, that same cell is going to drop out on you which will give you a premature LVC, or it could run so low that it dies painfully and takes your truck out with it. At most, I'd only run it a minute, then unplug and check the cell voltage to see where it is.

I've had a few packs die on me over the past couple of years and normally just one cell goes bad. Usually, if I charged them, then let the pack sit overnight, check the voltage in the morning, the bad cell would have dropped considerably. When that happens, you shouldn't use the pack anymore.

If your careful, you can disassemble the pack and make a 2S pack out of it. I've done that a few times, but it was to take 3 2S packs to make 2 3S packs. You need a high wattage iron though as the solder they use is high silver I think and there's a lot of it, so a 50W iron won't touch it. It will just make it hot. I bought a cheap 100W iron and it makes short work of them.

A 3S pack I made out of SMC 7200mah 2S packs:

That wasn't the end result, that was just after soldering. I put protective layers of tape under the wires so they wouldn't short out on anything and behind the battery tabs for support.

SMC uses 2S2P for the packs I had, which is 4 cells total, two in parallel, then 2 pairs in series. Was a bit of a pain dealing with that, but I made it work and have been using the "3S" packs I built for the past 6 months or so in my smaller trucks.

I used the plastic case halves to protect the top/bottom of the pack and just wrapped it with fiber tape really well.

To go from 3S to 2S, you would need to get some 2S charge plugs. Although, a 3S charge plug might work if you hook it up right. I just bought some spare 2S and 3S plugs for when I did this and in case I rip off a 2S plug when out bashing. They are cheap enough.

Thanks for all that info. After careful consideration, I will probably just drain and trash it. A 2S lipo isn’t that much to buy if I really need one. In the grand scheme of things, burning down a rig at minimum isn’t worth it.

 

[SrC]

Check your punch level in the esc. Trim it down to see if yu get diff. Results. Also, check the resistance of each cell as well as the balance volts of each cell. LVC will trigger if just one cell dumps rapidly. I have purchased dud lipos before. It can happen to high end or low end brands of lipos.
But def check the ohm restate of each cell. If anyone cell is above 5-6 ohms you have a dud for a lipo pack. New lipos are balanced easily and have low impedence below 4 ohms as a general rule. But all cells should all be of similar resistance.
Sometimes even the C rating on the cells are not true and accurate. What you are experiencing replicates using a 15c lipo in a high amp draw setup. LVC engages too rapidly. A 30 second rest and it has power again to run briefly.

 

[jondilly1974]

I’ve got it sorted now. My one 3S lipo has a bad cell and the new Orvonics 7600 wasn’t getting a full charge due to my charger setting was set to a max of 5000mah.

 

[olds97_lss]

I’ve got it sorted now. My one 3S lipo has a bad cell and the new Orvonics 7600 wasn’t getting a full charge due to my charger setting was set to a max of 5000mah.

Ah, I didn't catch that charger setting you mentioned. I have mine set to the max size packs I have and I'm usually in the room any time I'm charging anything, so if it runs longer than it should, I'm there anyway. I have some 10500 2S packs, so that's what I set my limit to, even though I mostly use 5000-7400 packs.