HELP PLEASE I think I may have some bad cells

[Fallingaway]

My test is almost done, and my neck cell is almost fully charged. I am going to Houston for the night; I will let the cell rest and see what it’s resting voltage is. I will post the resting voltage

Patients grasshopper
View attachment 34314

awesome! I’m glad they’re testing that good! Keep the updates coming. Also, could you share where you bought them from? A link preferably. Thanks

 

[Moltensurf]

I agree with your points. I’ve had those cells in 100a and they were great! Was just curious of why in his particular situation.

I am putting these cells together to make a bank for my ram pro master, I am converting. I used to live on a sailboat, and had a battery bank made up of 6 golf cart batteries. These are way better. Those golf cart batteries weigh a ton. I had 530 watts of panels on my boat with a morning star mppt.

 

[Moltensurf]

I ran the batteries down to 2.5 V using my meter at the terminals. Here are the final results on the cell

 

[Moltensurf]

Nice! I think your goi g to hit your rated capacity or really close to it. Hey just curious. Why did you go with the 200a? From what I’ve been seeing the 280s are a much better deal

To be quite honest,I did not find this forum until after I ordered the batteries.I could have used a few more amp hours, but this will be OK. That is still a lot of amp hours For my needs.

 

[Fallingaway]

I am putting these cells together to make a bank for my ram pro master, I am converting. I used to live on a sailboat, and had a battery bank made up of 6 golf cart batteries. These are way better. Those golf cart batteries weigh a ton. I had 530 watts of panels on my boat with a morning star mppt.

Oh nice! Love to follow your build with that too. Is it going to be for camping/living or you going to work out of it?

 

[Moltensurf]

Oh nice! Love to follow your build with that too. Is it going to be for camping/living or you going to work out of it?

It’s going to be built to camp out of and live out of. I want to mount everything inside where it can be easily taken out if needed. They have this stuff called 8020 aluminum it is really killer stuff to work with

 

[Just John]

View attachment 34321
I ran the batteries down to 2.5 V using my meter at the terminals. Here are the final results on the cell

That looks like you got what you paid for. My 280AH cells test out to 275 to 281AH. Your first attempt shows 108% of rated capacity. That's a quality cell.

 

[Just John]

It’s going to be built to camp out of and live out of. I want to mount everything inside where it can be easily taken out if needed. They have this stuff called 8020 aluminum it is really killer stuff to work with

Nice, I looked up that 80/20 aluminum, that is impressive. Might make it easy to build some portable solar panel frames, I will investigate. Thanks for the tip!

 

[Moltensurf]

Nice, I looked up that 80/20 aluminum, that is impressive. Might make it easy to build some portable solar panel frames, I will investigate. Thanks for the tip!

I have some attachments I put on my roof that allow me to put that 8020 on my roof and make a rack

 

[Dzl]

In retrospect, now that you have completed a full single cell capacity test on a single cell and got over rated capacity, what do you think skewed/screwed up your first test showing so much less capacity?

 

[GSXR1000]

From the pictures I believe what people are referring to as a "heater" here is a capacity tester like this one it should have a wide voltage input range

FYI top changing will take 7-14 days if ran 24 hours a day

 

[snoobler]

I am putting these cells together to make a bank for my ram pro master, I am converting. I used to live on a sailboat, and had a battery bank made up of 6 golf cart batteries. These are way better. Those golf cart batteries weigh a ton. I had 530 watts of panels on my boat with a morning star mppt.

Do you plan to use this battery to start an engine?

 

[Dzl]

From the pictures I believe what people are referring to as a "heater" here is a capacity tester like this one it should have a wide voltage input range

FYI top changing will take 7-14 days if ran 24 hours a day

These testers are only for discharging

 

[Moltensurf]

@Moltensurf what did the cell settle to before you started to discharge it?

The last cell I charged sat for 24 hrs it was holding at 3.52 v

 

[John Frum]

The last cell I charged sat for 24 hrs it was holding at 3.52 v

A sell can't settle if you are holding it at a voltage.

 

[Moltensurf]

A sell can't settle if you are holding it at a voltage.

It was fully unplugged.

 

[Just John]

The last cell I charged sat for 24 hrs it was holding at 3.52 v

That is about where my fully charged cells settle to.

 

[Moltensurf]

I’ve tested 8 cells so far they all exceed vendors amp hour specs. Can I hook up my 24 volt bms, and test the last pack with the cells wired into a 24 volt battery? I was thinking I could use a light bulb for a load, and check the amp draw with my dc amp clamp? I know, Patience grasshopper. But I have these guys from China hanging around waiting to get paid.

 

[Just John]

I’ve tested 8 cells so far they all exceed vendors amp hour specs. Can I hook up my 24 volt bms, and test the last pack with the cells wired into a 24 volt battery? I was thinking I could use a light bulb for a load, and check the amp draw with my dc amp clamp? I know, Patience grasshopper. But I have these guys from China hanging around waiting to get paid.

If you have a BMS hooked up, it is safe. Be aware that the state of charge is unknown, so charge the pack until one cell is at high voltage disconnect, then parallel them to get them all fully charged before testing as a pack. Sounds like you got what you paid for.

 

[Moltensurf]

If you have a BMS hooked up, it is safe. Be aware that the state of charge is unknown, so charge the pack until one cell is at high voltage disconnect, then parallel them to get them all fully charged before testing as a pack. Sounds like you got what you paid for.

If I test them as a pack, with the BMS hooked up. I will get a full read out of each individual cell? Will I be able to tell if there is a problem with a cell? Or do I need to drain them all down one at a time?