Building a battery pack with super glue?

[Darren2018]

Hi,

I am building a 70 cell 30Q Hailong pack and I was wondering if super glue (Cyanoacrylate) is safe to use on the cell wraps? I would have used hot glue but due to the limited space in the Hailong case I can't as I need space for the BMS. I searched Google and it appears to be safe but I am also concerned about the heat from the cells. If it's compatible then I shall use Cyanoacrylate to tack the cells together and then hot glue and wrap the whole pack once I have the cells in order but I wanted to make sure there have not been any known disasters by doing this .

 

[purduephotog]

I can't speak to the wraps, but please don't. Super glue is not structural and WILL fail. It's a fast hold. Use it to perhaps hold something in place while another glue (epoxy?) seals.

Superglue will fail over time and sometimes faster than you'd expect.

For instance, when building little jigs I'll use it with wood glue. 1 spot of superglue to hold the parts together while the wood glue cures.

 

[Darren2018]

Good idea. The thing I am worried about are the cell wraps rupturing due to a reaction over time on the PVC wrap, I have opened old laptop packs that have suffered from this type of failure. I'm guessing it should be ok for a few years at least.

 

[amberwolf]

Generally, Cyanoacrylates are crystalline when cured, and will fracture under vibration and thermal cycling.

Decades ago, I used to scratchbuild plastic / etc models, and often used various CA types to glue non-plastic bits to them. Over time, often only months, sometimes weeks, those bits would begin to fall off, sitting inside non-sealed display cases in a hobby store where they weren't touched, but were exposed to overnight temperatures significantly warmer or cooler than the daytime (when the A/C or heat would be running during business hours, but shut completely off afterhours). It didnt' happen on every part, but enough of them that I started using epoxies instead, only using CAs as temporary "test the idea" glues.

 

[Darren2018]

Would you say that epoxy is a safer option then? The thing is there are so many different types.

 

[mistercrash]

I made a large battery with CA glue and the wraps just tear after a short while on some of the cells, or the CA cracks and breaks apart, the only thing holding those cells was the nickle strips. I made another battery with hot glue and the wraps were not damaged but the some of the cells came apart, the only thing holding those cells together was the nickle strips. I made another battery using clear silicon for caulking, the one that smells like vinegar and sticks too almost anything. This was very good at holding the cells together, and the cells can be taken apart without ripping the wraps. It holds much better than hot glue and does not become brittle like CA glue or epoxy. But it needs to cure for a while.

 

[Darren2018]

I made a large battery with CA glue and the wraps just tear after a short while on some of the cells, or the CA cracks and breaks apart, the only thing holding those cells was the nickle strips. I made another battery with hot glue and the wraps were not damaged but the some of the cells came apart, the only thing holding those cells together was the nickle strips. I made another battery using clear silicon for caulking, the one that smells like vinegar and sticks too almost anything. This was very good at holding the cells together, and the cells can be taken apart without ripping the wraps. It holds much better than hot glue and does not become brittle like CA glue or epoxy. But it needs to cure for a while.

I did think of using silicone but the problem is dispensing it. How would you dispense silicone as finely as CA or even hot glue?? I might try thin double sided tape, I only need to tack the cells together so I can get the main adhesive and outer PVC heat shrink on which I am hoping will hold the pack together firmly.

 

[999zip999]

Do not contact one set of cells in series with another set of cells in series can cause short

 

[mistercrash]

I made a large battery with CA glue and the wraps just tear after a short while on some of the cells, or the CA cracks and breaks apart, the only thing holding those cells was the nickle strips. I made another battery with hot glue and the wraps were not damaged but the some of the cells came apart, the only thing holding those cells together was the nickle strips. I made another battery using clear silicon for caulking, the one that smells like vinegar and sticks too almost anything. This was very good at holding the cells together, and the cells can be taken apart without ripping the wraps. It holds much better than hot glue and does not become brittle like CA glue or epoxy. But it needs to cure for a while.

I did think of using silicone but the problem is dispensing it. How would you dispense silicone as finely as CA or even hot glue?? I might try thin double sided tape, I only need to tack the cells together so I can get the main adhesive and outer PVC heat shrink on which I am hoping will hold the pack together firmly.

I only informed you of what worked best for me to make a battery with can cells stuck together. I learned a few things since then about DIY battery packs and I would not try making a battery with can cells stuck together in any way or even with the cells holders available on the market today.

 

[Darren2018]

:lol: Read my post again.

 

[mistercrash]

right back at you. Good luck.

 

[Darren2018]

:wink: