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DIY Powerwall Builders Are Using Recycled Laptop Batteries to Power Their Homes

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Re: DIY Powerwall Builders Are Using Recycled Laptop Batteries to Power Their Homes

#31

Post by princekolt »

Baeocystin wrote: post #4
ficklepickle wrote: post #3

This sounds like it could be rather dangerous, no? Connecting up a bunch of old lithium cells of unknown origin and using them hard. I'd also worry about an insurance claim being denied if it burned my house down. However, I very much approve of the DIY ingenuity and repurposing of old stuff.

Kind of dangerous seems like quite the understatement, considering the nature of lithium batteries! It'd be fun to play with something like this for the learning, but I wouldn't actually run one unless it was in its own shed, many dozens of yards from the nearest anything else. Lithium fires are no joke.

I've read claims (theoretical and practical) from both sides, so apparently the safety of lithium cells can vary widely based on manufacture quality and maintenance.

But also, on the video, they shows each pack of cells he uses has individual over and underchange and temperature sensors, so the system is able to tell if any individual section is going bad. It's a pretty neat, and external installation, so I don't think it is very harmful on a "massive heat incident".

Re: DIY Powerwall Builders Are Using Recycled Laptop Batteries to Power Their Homes

#32

Post by foota »

userbinator wrote: post #23
Reason077 wrote: post #21

Earlier quoted context omitted.

Unrepairable black boxes? This isn't really true of Tesla. Sure, it would be nice if they could make service manuals and service parts more freely available, but the same could be said of all car manufacturers. There are guys on YouTube who have re-built entire Teslas from near-scratch using salvaged parts from multiple vehicles. Guys with no formal training and no previous experience with EVs. Tesla does not do anyt…

Tesla does not do anything to make their cars hard to repair. I'm not in the EV or Tesla communities, but I remember reading something about "activation" being required?

This could be because of the packaged services that come with the Tesla?

Re: DIY Powerwall Builders Are Using Recycled Laptop Batteries to Power Their Homes

#33

Post by extr »

Reason077 wrote: post #25
hwillis wrote: post #12

Earlier quoted context omitted.

Theres no way to detonate a pack like this. 18650s have a pressure release, so the cstch fire but dont explode. In the very unlikely event that fails, a cell could burst, but it cant cause other cells to burst unless the entire pack failed to vent under extreme pressure.

Yeah. It's a total misconception that Lithium batteries can "explode". Sure, there's a fire risk if you have faulty or unprotected cells. But there's no explosion risk unless there's something very wrong with the way they're packaged.

Semantics. Is a battery undergoing thermal runaway/venting "exploding"? Or merely "ejecting scorching hot gas and catching fire?" Maybe it's not blowing up like an IED, but either way I don't want it happening in my garage.

Re: DIY Powerwall Builders Are Using Recycled Laptop Batteries to Power Their Homes

#34

Post by userbinator »

extr wrote: post #27
alasdair_ wrote: post #24

Earlier quoted context omitted.

>There's a reason that 18650s aren't generally sold directly to consumers https://www.amazon.com/gp/aw/s/ref=is_s?k=18650 has pages of them. The last flashlight I bought requires them too.

Yeah, I'm aware you can buy them. I have 4 cells sitting in front of me right now. But there is a big difference between someone specifically buying them for use in a high-discharge device like a flashlight or vaporizer versus picking up a pack at Walmart next to the AA/AAA. Because of the high discharge you can hurt yourself or start a fire much more easily. Just look at the stories of people with burns on their thi…

But there is a big difference between someone specifically buying them for use in a high-discharge device like a flashlight or vaporizer versus picking up a pack at Walmart next to the AA/AAA

You can find 18650s for sale on walmart.com . I'm not sure if the physical stores carry them, because there aren't any where I live, but I know that in Shenzhen/HK and other parts of Asia you can easily find 18650s for sale amongst other batteries in physical stores.

Because of the high discharge you can hurt yourself or start a fire much more easily. Just look at the stories of people with burns on their thighs from throwing them into a pocket with keys/change.

NiCd/NiMH can also source huge currents if shorted.

Re: DIY Powerwall Builders Are Using Recycled Laptop Batteries to Power Their Homes

#35

Post by jjeaff »

ficklepickle wrote: post #3

This sounds like it could be rather dangerous, no? Connecting up a bunch of old lithium cells of unknown origin and using them hard. I'd also worry about an insurance claim being denied if it burned my house down. However, I very much approve of the DIY ingenuity and repurposing of old stuff.

Luckily, home owners' insurance covers stupidity as well as acts of God. So as long as there is no evidence of intentional arson, then insurance would have to pay.

Re: DIY Powerwall Builders Are Using Recycled Laptop Batteries to Power Their Homes

#36

Post by hwillis »

extr wrote: post #33
Reason077 wrote: post #25

Earlier quoted context omitted.

Yeah. It's a total misconception that Lithium batteries can "explode". Sure, there's a fire risk if you have faulty or unprotected cells. But there's no explosion risk unless there's something very wrong with the way they're packaged.

Semantics. Is a battery undergoing thermal runaway/venting "exploding"? Or merely "ejecting scorching hot gas and catching fire?" Maybe it's not blowing up like an IED, but either way I don't want it happening in my garage.

The difference between "can be ignited" and "massive bomb" is not semantics. Even new pouch cells are way safer than they used to be. Unregulated 18650 cells are quite safe if the correct circuitry is used. The only dependable way to ignite them is to smash completely open them at full charge.

Re: DIY Powerwall Builders Are Using Recycled Laptop Batteries to Power Their Homes

#37

Post by JustSomeNobody »

extr wrote: post #13
cyphar wrote: post #2

One of the really disappointing things about Tesla is how incredibly proprietary all of their products are. For a company that has such lofty goals as "saving the world", it feels wrong to me for them to then sell DRM cars and unrepairable black boxes. Maybe I'm just too idealistic, but surely if we have an opportunity to create a new market for solar devices why would we decide to recreate the proprietary world of t…

This isn't unique to Telsa, all vehicles are becoming more difficult to repair as computers and software replace what used to be handled by mechanical systems. I would actually much prefer to drive next to a Tesla knowing that the guy behind the wheel (potentially staring into space as it drives itself) hasn't implemented any "hacks". A similar argument exists for why DIY battery banks are not ideal. It's not inconce…

About the same as I feel about 95% of software running on the internet being copied from StackOverflow. Rather Meh. I would worry if the engineers at Boeing did it, but a bunch of crappy javascript apps running on the web? No. As for the neighbor, I don't live on a zero lot line, so let him burn his house down all he wants.

Re: DIY Powerwall Builders Are Using Recycled Laptop Batteries to Power Their Homes

#38

Post by jaggederest »

Reason077 wrote: post #25
hwillis wrote: post #12

Earlier quoted context omitted.

Theres no way to detonate a pack like this. 18650s have a pressure release, so the cstch fire but dont explode. In the very unlikely event that fails, a cell could burst, but it cant cause other cells to burst unless the entire pack failed to vent under extreme pressure.

Yeah. It's a total misconception that Lithium batteries can "explode". Sure, there's a fire risk if you have faulty or unprotected cells. But there's no explosion risk unless there's something very wrong with the way they're packaged.

https://www.youtube.com/watch?v=Md4l9bFDOtc

That, to my untrained eye, looks like enough batteries to take down nearby structures if they went up, and packaged in such a way that a runaway in one cell that caused it to vent would propagate to other cells nearby.

Granted they're pretty reasonably protected by 2-3 layers of electronic monitoring and on-cell fuses, but lord, a small fire would burn the neighborhood.

I think all that it would take to render them marginally safer is a firewall between the different packs made of some good steel or refractory material.

Re: DIY Powerwall Builders Are Using Recycled Laptop Batteries to Power Their Homes

#40

Post by extr »

hwillis wrote: post #36
extr wrote: post #33

Earlier quoted context omitted.

Semantics. Is a battery undergoing thermal runaway/venting "exploding"? Or merely "ejecting scorching hot gas and catching fire?" Maybe it's not blowing up like an IED, but either way I don't want it happening in my garage.

The difference between "can be ignited" and "massive bomb" is not semantics. Even new pouch cells are way safer than they used to be. Unregulated 18650 cells are quite safe if the correct circuitry is used. The only dependable way to ignite them is to smash completely open them at full charge.

Cool, you caught me being hyperbolic. They are not literally a massive bomb.

> Even new pouch cells are way safer than they used to be.

Right, because these packs filled with recycled cells are going to have the latest protections.

> Unregulated 18650 cells are quite safe if the correct circuitry is used.

Which is my whole point, I'm not sure I trust the guy down the street to correctly wire and have adequate circuit protection for his DIY battery pack in his garage.

> The only dependable way to ignite them is to smash completely open them at full charge.

https://www.youtube.com/watch?v=24fYrV2vCPk

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