Accidental overcharge, what do I do now?

[Xerxes]

Good point. I decided to top balanced in parallel but I got a little greedy and set the voltage to 3.7 5A. This turns out to be the 100% setting of my dc variable charger, which increased the voltage as the battery also reached a higher voltage.

tl;dr: stick with 3.6V b/c the charger won't stop increasing the voltage

EDIT: used the UNIROI 5A dc variable charger https://www.amazon.ca/dp/B07D279WR8/ref=emc_b_5_t

Did anyone read the reviews photo on this power supply showing a 1 Volt peak to peak high frequency noise on this sucker!

Just thinking.....what would that mean to your battery charging adventure. They would act like a big capacitor to flatten out the noise...... but ..........

 

[Ampster]

Pray tell the tale of the overcharged "8 cells in parallel"

I mentioned it in another thread but it is worth repeating and illustrates the value of being patient and not taking short cuts. Normally I charge a pack in parallel with an inline meter that tells me volts, Amps and Ahrs. Mine was not working and my spare was not available. I checked the voltage setting of the power supply and it was set to 3.8 volts. I didn't change it because it took a particular philips head screwdriver which was 20 feet away somewhere in my rollaway tool chest. Besides, this process was going to take many hours and I could make that adjustment later. I did regularly check as the voltage slowly incremented upward but was no where near my target of 3.5 for the first stage. Then my daughter called, I got distracted and when I finally got back they were at 3.8. I quickly put a load on them until they came back to 3.5.

 

[denweny]

Man, double-checked and it swelled. Doesn't even fit my battery enclosure anymore. Is it still safe to use?

 

[NoSmokeYet]

Get rid of those LiPo batteries and buy some good Deep Cycle batteries. Make life a little easier?

 

[MisterSandals]

Man, double-checked and it swelled.

How badly? Any pix?
Might be a good idea to try to contain it somehow in case it wants to keep expanding. Boards and clamps might be quick and easy.

But I am also curious as to how/if it holds a charge and whether its safe to use. You may be on the frontier on this, i do not recall anybody pushing them up that high.

 

[Ampster]

Get rid of those LiPo batteries and buy some good Deep Cycle batteries. Make life a little easier?

He has LFP (LiFePO4) and they may still have some capacity.

 

[Ampster]

You may be on the frontier on this, i do not recall anybody pushing them up that high.

He started the thread when he over charged his cells balancing them. Unfortunately he didn't have anything to pull them down except his girlfriends headlights and that plan was nixed. They stayed too long in that state and now we have some puffies.

 

[NoSmokeYet]

He has LFP (LiFePO4) and they may still have some capacity.

I just group all those battery bombs into one group "LiPo" ?

 

[Ampster]

I just group all those battery bombs into one group "LiPo" ?

You may want to rethink that assumption since most people think LFP is one of the safest chemistries. I understand that you are fond of Pb.

 

[Sojourner1]

I just group all those battery bombs into one group "LiPo" ?

Ahh... to be ignorantly bliss.

 

[Gazoo]

Man, double-checked and it swelled. Doesn't even fit my battery enclosure anymore. Is it still safe to use?

What do you mean it swelled? Did all the batteries swell or only one, and how badly.

 

[Xerxes]

What do you mean it swelled? Did all the batteries swell or only one, and how badly.

Maybe the batteries saw its girlfriend in a bikini so the swelling is normal .........and can be relieved by some vigorous suction....

Sorry.....its late on a Saturday night and I could not resist the great setup .......

 

[Pierre]

He started the thread when he over charged his cells balancing them. Unfortunately he didn't have anything to pull them down except his girlfriends headlights and that plan was nixed. They stayed too long in that state and now we have some puffies.

? You are lucky ! a Puffy here is a deadly snake ?. Sorry for your loss. You will have to do some LiPO suction

 

[Pierre]

Maybe the batteries saw its girlfriend in a bikini so the swelling is normal .........and can be relieved by some vigorous suction....

Sorry.....its late on a Saturday night and I could not resist the great setup .......

 

[denweny]

What do you mean it swelled? Did all the batteries swell or only one, and how badly.

How badly? Any pix?
Might be a good idea to try to contain it somehow in case it wants to keep expanding. Boards and clamps might be quick and easy.

But I am also curious as to how/if it holds a charge and whether its safe to use. You may be on the frontier on this, i do not recall anybody pushing them up that high.

All eight 150AH 3.7v cells swelled. I luckily got them for $900 total pre-covid, but holy cow prices have 2.5x'd since.
I don't have any pics since I forced it back into my box, but imagine eight blue cells with a 30% bulge on both sides.

I think I'm going to try and continue to use this as-is for my full-time vanlife conversion (fridge, heater, fan, laptop).
Now that I have a BMS and inverter, I'll do a capacity test on it with a 120v fridge and let you know how it goes.
Hopefully, the worst case is that I'll buy 100AH car battery should this die on the road.

 

[Gazoo]

That's a shame. I will be curious about the capacity left. I can't comment on how safe they are but personally with that much bulge I wouldn't use them. I am in the process of ordering 4 280ah cells...total cost will be around $400.00. Hopefully all goes well with that. Thanks for the update.

 

[denweny]

That's a shame. I will be curious about the capacity left. I can't comment on how safe they are but personally with that much bulge I wouldn't use them. I am in the process of ordering 4 280ah cells...total cost will be around $400.00. Hopefully all goes well with that. Thanks for the update.

Oh wow, that's super cheap. Who and how are you buying that?

 

[Gazoo]

Follow this thread.

What are the main brands of LFP batteries sold in China

The largest battery manufacturers in China are CATL and BYD, both of which have very good quality, but CATL prefers NCM batteries and BYD prefers LFP batteries However, the shape of BYD's battery is not popular. People are more interested in the CATL shape of the battery. In addition to...

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