Comment by koolba

Comment by koolba 3 days ago

25 replies

While very interesting, that seems like it would be one hell of a fire hazard as well. Especially for the ones that are tightly packed in the middle of each bundle.

theandrewbailey 2 days ago

> This growth forced the creator to build a separate warehouse, located about 50 meters from his home, to store the batteries and the new charge controllers and inverters.

The hazard appears to be accounted for.

  • TheBlight 2 days ago

    Yeah wind has never been known to blow fires 50 meters.

    • [removed] 2 days ago
      [deleted]
    • timbit42 2 days ago

      How do you know the prevailing wind direction in his location?

      • PhunkyPhil 2 days ago

        How do you know that a favorable wind direction will eliminate the risk of a fire hazard?

johnisgood 3 days ago

> Despite being an unusual system, with recycled and homemade components, no major problems have been reported, such as fires or swollen batteries, which is a common issue with some second-hand electronic devices.

That said, one should be prepared for it.

  • rtkwe 2 days ago

    AFAIK 18650s like he's using never swell as they're in hard metal shells not pouches like most consumer electronics, so they don't have the ability to swell until they're catastrophically damaged. He's built a small building 50m away from his house to hold it anyways so it can probably be safely allowed to just burn, it's not like fire departments have much better options than waiting for it to burn out and hoping it doesn't reignite anyways.

    • bigfatkitten 2 days ago

      > AFAIK 18650s like he's using never swell as they're in hard metal shells not pouches like most consumer electronics, so they don't have the ability to swell until they're catastrophically damaged.

      They do swell, but they swell at the terminals rather than at the sides.

tomxor 3 days ago

They don't look tightly packed compared to the constraints of being inside laptops and phones where they are given millimetres to expand.

misnome 3 days ago

Yeah, my first thought on reading the article was that it didn’t detail his fire control systems..

  • rtkwe 2 days ago

    That's the neat part about lithium fires you just can't, they're self oxidizing so there's not much you can do to definitively put them out the best option is usually to flood them with water to cool them down and contain the damage they cause.

    • em3rgent0rdr 2 days ago

      Yeah. Commercial home solar battery power as I understand is done with safer chemistries, such as lithium iron phosphate, which while they have a lower energy density (which is not a big downside for a stationary building) don't have the thermal runaway issues that labtop lithium ion batteries have. I wouldn't want to live next door to the DIY labtop battery array enthusiast.

      • rtkwe 2 days ago

        He seems to be doing it fairly safely by having it housed in a building a whole 50m away from the main dwelling. A fire from there could spread to the house or elsewhere but it's no longer a metal fire so it's a lot easier to deal with and just contain the fire in/around the shed. I'd probably add a nice gravel buffer around it to help that and live in a reasonably well hydrated part of the country so there's not as big a fire risk from embers.

        • em3rgent0rdr 2 days ago

          Great if you are a skilled electrical engineer who owns a bunch of land somewhere that doesn't have any fire risk.

  • extrapickles 2 days ago

    They keep the power pack in a shed away from anything too flammable. They could lose the shed, but it would be unlikely to take the house with it.

elif 2 days ago

My thoughts as well, and that's coming from someone who sleeps directly above 2 powerwalls

  • bee_rider 2 days ago

    Sounds like it is out in a shed.

    Also the guy who made this battery pack has the incentive to not burn down his house, whoever made yours has the incentive of one more day on the assembly line… I dunno, wouldn’t judge him too harshly.

    • em3rgent0rdr 2 days ago

      Commercial solar home battery use safer battery chemistries which don't experience thermal runaway like lithium ion labtop batteries do..