5 ms·

There is a lot of information on this on the diysolarforum.com but if you purchase name brand cells, CATL/EVE from a good supplier these are the same ones used

There is a lot of information on this on the diysolarforum.com but if you purchase name brand cells, CATL/EVE from a good supplier these are the same ones used by all industry. They have a very good track record. I do not advocate buying from any random seller on aliexpress. There are not any mass market non-chinese batteries available for sale. Virtually all solar equipment of any fashion is chinese made.

Aurornis 2y ago
That’s the forum I followed. The failures often came from BMS or other parts, too. There’s a lot of focus on the cells, but people are buying whole packs with a BMS.
- h0l0cube 2y ago
  Then that’s more the issue with the BMS rather than the cells
  - samatman 2y ago
    Problems with the BMS can become problems with the cells very quickly.
    - h0l0cube 2y ago
      Yeah, but I would just buy the cells and spend more on a BMS. Or you can just use a low voltage cutoff and an active balancer for a smaller setup
  - Aurornis 2y ago
    In many of the systems, the BMS and battery are one in the same. This article blurs the lines between the cells and battery system, too.
    - h0l0cube 2y ago
      The post you were replying to was specifically about cells, and if you’re going for economy, building your own packs are substantially cheaper than buying packs domestically. Also less fraught when you’ve DIYed to diagnose and fix when things go wrong
      - lazide 2y ago
        Also prone to average people setting themselves or their houses on fire, eh?
        h0l0cube 2y ago
        Depends on how scrupulous Average Person is being. There's codes for electrical and solar installations that can be followed, and it's best to stick to the letter, even if you're certain it doesn't apply. And after that, you should get it certified by a licensed professional, but would also need a licensed professional to hook it up to the grid
        lazide 2y ago
        I think you’re misunderstanding what I’m trying to say. I’m talking about assembling your own multi-kwh lithium battery assemblies (pre-BMS even). One wrong poke with a screwdriver, and all sorts of entertainment is likely to ensue eh? And they’re big enough, no portable fire extinguisher is going to make a dent either.
        defrost 2y ago
        Sure, you're saying some people shouldn't DIY. Where I live many people DIY as a great many people have mad skills (lots of FiFo workers making a good living from O&G installions and big mining projects). They build their own houses, their own planes, off grid power systems, water proof EV's to drive across harbour floors, etc. If you've got a big (shipping container sized) battery pack you need a big thermal blanket to cut off the oxygen or a wide enough fire break about it. Speaking of DIY home builds, here's a good use of black builders plastic: https://www.youtube.com/watch?v=1ILbQHnHPnY https://www.youtube.com/watch?v=1ILbQHnHPnY
- jauntywundrkind 2y ago
  I buy that the bms aren't very good and are drastically hurting your system. Much lower key stakes, but I have an Andis Supra trimmer I rely on a lot, but it's charger has basically no low key mode: it will pump 10W+ power into these 2S cells forever. It's criminally bad battery management, will absolutely nuke the heck out of these high end cells, if you forget to pull it off the charger. To me, the main thing is observability. Too many people trust their systems. We need to see how things are going. As the voltage converges to peak, we should be seeing the amps level out. We can't just trust the machines, ever. We need to be observant. Ultimately I think we'd be able to review & get rid of bad equipment more effectively, but we should be in tune with what these systems are doing, should be aware that - oh hell - we are at peak voltage and still pushing power in, and we need to stop. These systems need to report what they are doing. Being blind consumers makes the economic system weaker; these systems should all report what they are doing.

Aurornis 2y ago

That’s the forum I followed. The failures often came from BMS or other parts, too. There’s a lot of focus on the cells, but people are buying whole packs with a BMS.

h0l0cube 2y ago
Then that’s more the issue with the BMS rather than the cells
- samatman 2y ago
  Problems with the BMS can become problems with the cells very quickly.
  - h0l0cube 2y ago
    Yeah, but I would just buy the cells and spend more on a BMS. Or you can just use a low voltage cutoff and an active balancer for a smaller setup
- Aurornis 2y ago
  In many of the systems, the BMS and battery are one in the same. This article blurs the lines between the cells and battery system, too.
  - h0l0cube 2y ago
    The post you were replying to was specifically about cells, and if you’re going for economy, building your own packs are substantially cheaper than buying packs domestically. Also less fraught when you’ve DIYed to diagnose and fix when things go wrong
    - lazide 2y ago
      Also prone to average people setting themselves or their houses on fire, eh?
      - h0l0cube 2y ago
        Depends on how scrupulous Average Person is being. There's codes for electrical and solar installations that can be followed, and it's best to stick to the letter, even if you're certain it doesn't apply. And after that, you should get it certified by a licensed professional, but would also need a licensed professional to hook it up to the grid
        lazide 2y ago
        I think you’re misunderstanding what I’m trying to say. I’m talking about assembling your own multi-kwh lithium battery assemblies (pre-BMS even). One wrong poke with a screwdriver, and all sorts of entertainment is likely to ensue eh? And they’re big enough, no portable fire extinguisher is going to make a dent either.
        defrost 2y ago
        Sure, you're saying some people shouldn't DIY. Where I live many people DIY as a great many people have mad skills (lots of FiFo workers making a good living from O&G installions and big mining projects). They build their own houses, their own planes, off grid power systems, water proof EV's to drive across harbour floors, etc. If you've got a big (shipping container sized) battery pack you need a big thermal blanket to cut off the oxygen or a wide enough fire break about it. Speaking of DIY home builds, here's a good use of black builders plastic: https://www.youtube.com/watch?v=1ILbQHnHPnY https://www.youtube.com/watch?v=1ILbQHnHPnY
jauntywundrkind 2y ago
I buy that the bms aren't very good and are drastically hurting your system. Much lower key stakes, but I have an Andis Supra trimmer I rely on a lot, but it's charger has basically no low key mode: it will pump 10W+ power into these 2S cells forever. It's criminally bad battery management, will absolutely nuke the heck out of these high end cells, if you forget to pull it off the charger. To me, the main thing is observability. Too many people trust their systems. We need to see how things are going. As the voltage converges to peak, we should be seeing the amps level out. We can't just trust the machines, ever. We need to be observant. Ultimately I think we'd be able to review & get rid of bad equipment more effectively, but we should be in tune with what these systems are doing, should be aware that - oh hell - we are at peak voltage and still pushing power in, and we need to stop. These systems need to report what they are doing. Being blind consumers makes the economic system weaker; these systems should all report what they are doing.