Batteryhookup EV CATL modules...taking two apart for the cells

[ScottLatimer]

I bought two 20 cell (280AH) modules from batteryhookup and these are new EV modules...I got the first module disassembled and unbolted only to find that CATL did a good job using some sticky stuff on the bottom of the 10 cell groups...I am trying to pull 10 cell subunits off whole and will cut it later to get the 24 V I am after...assuming I can unstick these things...I assume a pry bar against the prismatic cells to "lever them out" would not be prudent and result in some unwanted pyrotechnics...anyone pulled one of these EV modules apart and have an idea how to unstick these things...???

 

[SparkyJJO]

Probably need something to dissolve/release the adhesive. What is safe to do that with, I don't know. WD40?

 

[ScottLatimer]

Probably need something to dissolve/release the adhesive. What is safe to do that with, I don't know. WD40?

I put in an email to the dealer...apparently they bought a few truckloads of these-all new-price isn't bad 140/each for 280AH...hopefully some previous customer has been down this road and knows what to do...I thought about heating the bottoms to soften the glue but its a double metal base so I can get into it...no telling if acetone or some weird organic ester compound is needed...(I am/was a chemist)...ok...thanks for the idea...or spray ether...its outside on my truck bed so shouldn't be an explosion hazard...

 

[niktak11]

I put in an email to the dealer...apparently they bought a few truckloads of these-all new-price isn't bad 140/each for 280AH...hopefully some previous customer has been down this road and knows what to do...I thought about heating the bottoms to soften the glue but its a double metal base so I can get into it...no telling if acetone or some weird organic ester compound is needed...(I am/was a chemist)...ok...thanks for the idea...or spray ether...its outside on my truck bed so shouldn't be an explosion hazard...

$140/cell?. You can get grade A 280Ah cells for not much more.

 

[ScottLatimer]

These modules I am fighting with (now that I can see under all the wiring and plastic shrouds) are epoxied together, silicon glued to the base and not at all user friendly to disassemble...the company says these can be separated by cutting the busbars but they never tried it themselves is my guess...they are sorry for my difficulties...so I have two days in these now and have little to show but I am gaining a lot of experience and learning to use creative and colorful new words as expletives...I will keep those interested in this endeavor apprised of the sellers help or non-help...why would you advertise stuff like that and not have verified it or attempted it yourself...well I guess I will be the only one on planet earth who will know how to get these apart...arrrrgggghhhh...I just need to remove 2 cells off each bank of 10...is that asking a lot????

 

[ScottLatimer]

Probably need something to dissolve/release the adhesive. What is safe to do that with, I don't know. WD40?

Dow actually makes a solution to dissolve cured silicon...and of course finding someone who sells it is like pulling hens teeth...

 

[brum]

WD40 is water displacement, 40th formula. It is not solvent.

If the glue is soft and you can access it, try with the wires for cutting wood. I think they call it diamond cutting wire.

Post some pictures, so we can get an idea of what you are fighting with.

 

[lisalizajohn]

You may have just saved me a lot of frustration - I have been lusting over those, but I'm not up for a battle. Like you, I hoped it would be as easy as they described. If you hadn't posted, my novice arse would have been pretty unhappy next week - I'll be very interested in hearing how you end up handling it. Best of luck!

 

[42OhmsPA]

Cell pack in question.

New CATL Modules with 20x 3.2v 280ah Prismatic - 17.92kWh - $110-$120/cell

These modules are new in the crate, never touched. 100% automotive grade, not reject grade B or A-. These are the batteries that were not rejected by automotive quality control. Each crate has 2 modules. The only crate that was open was the one we opened for the photos. Each module has 20 cells...

batteryhookup.com

I was looking at these last night and came to the conclusion I'd just cut the busbar and base between 16/17 and make a 12v pack with the remaining 4. Then I realized I'd be better off ordering from 18650 or docan.

Back in my debadging automotive days I'd use a little goof off then come through with some fishing line or dental floss between the body panel and badge.

 

[niktak11]

Cell pack in question.

New CATL Modules with 20x 3.2v 280ah Prismatic - 17.92kWh - $110-$120/cell

These modules are new in the crate, never touched. 100% automotive grade, not reject grade B or A-. These are the batteries that were not rejected by automotive quality control. Each crate has 2 modules. The only crate that was open was the one we opened for the photos. Each module has 20 cells...

batteryhookup.com

I was looking at these last night and came to the conclusion I'd just cut the busbar and base between 16/17 and make a 12v pack with the remaining 4. Then I realized I'd be better off ordering from 18650 or docan.

Back in my debadging automotive days I'd use a little goof off then come through with some fishing line or dental floss between the body panel and badge.

Not a very good deal imo. They'd have to be under $100/cell for me to consider the trouble.

 

[brum]

If it was for me I would leave the pack as it is, use 18 of its cells the way they are connected, try to use the existing BMS, and go to voltage-based battery settings. 18S will be 62V when full and 54V when empty. The SMA Sunny Island works with voltages up to 63V and should do the job. Or just look for an inverter that can output up to 70V and can do the job.

You've already given the money. Try to use the existing pack with minimum modifications. But this will require research on what is actually possible.

 

[timselectric]

I looked at these, also. And decided that it wasn't a good enough deal, to justify the extra work.

 

[lisalizajohn]

Looks like they're selling them extracted piecewise - I went ahead and ordered eight, of you all tell me what to buy to adequately test them, I'm happy to help see how these 'true EV grade' cells stack up against what we can get through the 'A minus' and 'B grade' suppliers.

 

[timselectric]

Yup
They're taking them apart and selling them in pairs, now.
I guess that the full modules weren't getting enough interest.
I have zero doubt about their performance, and quality. And the price is also fair.
I'm sure that we will see a lot of people buying them, now.

 

[ScottLatimer]

If it was for me I would leave the pack as it is, use 18 of its cells the way they are connected, try to use the existing BMS, and go to voltage-based battery settings. 18S will be 62V when full and 54V when empty. The SMA Sunny Island works with voltages up to 63V and should do the job. Or just look for an inverter that can output up to 70V and can do the job.

You've already given the money. Try to use the existing pack with minimum modifications. But this will require research on what is actually possible.

I sorta have a machine shop---sorta---so I can make a jig to get these where I need them to be but as one posted previously, its a lot of trouble and buying cells with studs or bolt holes and not having to drill all these welded buss bars to accept cabling makes these less than ideal...new to this solar stuff...but so far everyone tested spot on voltage wise...not seen a single one vary by even a 1/10 th of a volt...regrettably I needed to take these apart because of location and size constraints for my project...two 8s2p's are for solar applications and a 8s for a gas engine to electric conversion of a 4x4 side by side...I just received a pallet (35) of Canadian bifacial Solar panels to play with...I am concerned that I might be developing a slight addiction to making my own power...I think we may need a link to a SolarAfficianados Recovery Group...