maybe we are being too critical because Lord knows they’re used at all kinds of applications. I think it’s reasonable to assume that they are selling them for vehicles that they’ve been tested to some degree by the manufacturer. I’m wondered if anybody knows if there are required safety test by the government if it’s really what you want, you are on the right track, just do the research.
But the one thing I will say from experience. Even if it’s a very slim chance, once one of those batteries starts burning, it is very difficult to put it out. It has a tremendous amount of stored energy and the fire creates oxygen so it’s hard to snuff it. When regular batteries go bad, even if they burn, it’s fairly contained.
Pre-post edit: sorry it's long. And to answer your second question first, there are definitely safety regulations about batteries and I guarantee you almost every offshore-manufactured battery out there skirts these regulations in one way or another.
It's a fair comment about being critical. I want to respond about why I'm very cautious, and then add a bunch of stuff that's intended for the OP mostly and anyone else who's interested.
Re: being critical. I have bought a lot of different kinds of batteries from China and other parts of the world, and it's an unfortunate fact that counterfeit cells are rampant in the ebay/aliexpress market universe. I've even bought cells from a couple reputable sources over the years where a batch of counterfeits slipped through. How Chinese mass production works is an interesting topic for another thread, but counterfeits/rejects/b-grade parts making their way into the pipeline is a fact of life.
These things that look like car batteries that these companies are selling are not car batteries inside. They're nothing at all like car batteries. They're boxes full of individual cells or flat pouches, all wired together in series and parallel and - this is very important - to a Battery Management System, a relatively complicated and _critical_ circuit board that makes sure the cells are charged (and sometimes discharged) properly. As with all things mass manufactured, these BMS vary in quality and reliability from bulletproof to downright dangerous.
If you look at the companies who supply these products, they're mostly from companies with names you've never heard of. If they get terrible ratings on Amazon or somewhere else, they'll just pop up next week under a different name. Safety concerns from these companies is maybe a topic for the tailgate but I've had more than a few knockoff products burst into flames or kill attached equipment over the years. Don't even get me started about these litter boxes that are killing cats - that's a sad statement on how some people think about safety, life, and profit.
I keep coming back to the same thought, which is that lead-acid batteries have been around 120 years in cars, they're proven tech, durable, reliable, very safe, and have a very long lifespan. These new battery chemistries are interesting, they have a very high energy density, but they've only been used in automotive applications in any numbers for 10-12 years. They're touchy, relatively fragile, expensive and rely on complex engineering (BMS) to keep them safe.
Long-winded as usual. Final thought, especially aimed at the OP - if it were me, I'd rather have a 500CCA battery with clean grounds, clean terminals, and healthy wiring than a 1000CCA battery without those things.
Anywhere your safety is concerned, buy products from known companies and trusted, reputable sources.
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