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

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91–100 of 183 posts

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

#91
post #46

I appreciate the engineering and time people are putting into these projects. I absolutely hate the way this article is portraying these people's work. These are not "consumers who can't afford commercially produced powerwalls." These are people who could probably work professionally in the field if they're not already. These projects are not "a little research, invested time, and a little ingenuity," they are the cu…

Amen to what you just said.

Years of effort and learning have culminated with these projects that they've undertaken and executed.

We should NOT undervalue that.

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

#92
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…

Tesla‘s are literally killer machines. Accessing the high voltage cables is not difficult (they are only covered by a plastic cover which is easily removable). Those power lines can easily kill you. Even if you are very careful, even a small mistake with the wiring can have fatal consequences. There is a reason why you are not allowed to do wiring and a lot of electronics in your house by yourself. I certainly hope t…

>Tesla‘s are literally killer machines.

So are all cars. Under-skilled people routinely (and legally) repair and maintain the systems that make these vehicles drivable (brakes, steering, suspension, etc).

Some folks are killed in doing so, much like any activity, but not any number that is out of proportion and typical with any activity where small mistakes can cost lives.

>There is a reason why you are not allowed to do wiring and a lot of electronics in your house by yourself.

That's not true in many places, much of the United States included. Only inspection is mandatory in most cases, barring specific regional laws. Again : Those that do their own work aren't just dropping like flies. A few accidents occur, but nothing of any proportion to require legislating more strict laws regarding such things.

>I can understand why Tesla does not want to take that risk.

My understanding of why Tesla acts the way they do has nothing to do with the complexity in their systems and danger in working around such complexity, but rather their interest in more protection for their IP, their desire for keeping customers within their own 'walled garden' of service options, and for controlling public perception of their product, all to the disservice of the customer (much like John Deere's behavior these past decade or two).

We aren't strangers to 'killer machines'. This isn't any new phenomenon. It's being framed that way by some to rationalize over-protective and controlling corporate behavior towards the consumer, and Tesla isn't alone in exercising such power.

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

#93
I wonder, they don't seem to put protection / monitoring circuitry in on the per-cell level (which would be prohibitively expensive). How do you know when a cell or a block of cells go bad? Or does it not matter?

I think it could be bad if the resistance of one increases and you have a bunch of them in series...

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

#95
post #57

Earlier quoted context omitted.

I really agree with you. The idea of a homebuilt powerwall sounds really cool. But it's not something I would come close to working with. Awhile ago I did a some volunteer work at a radio station. One of my tasks was to check for arcing. That involved going into the transformer room, disabling the safety systems, unracking some of the electrical components, powering the system on, turning off the lights and then look…

High voltage, sure, but outside of an inverter that you can/should buy prepackaged none of this needs to be high voltage. The system in the embedded video has 14 sets of cells in series, meaning 40-60 volts.

Danger of electrocution is not particularly high, but can easy start a serious fire with such batteries. The energy capacity with create a seriously hot arc if shorted, and there is a potential for thermal runaway of the battery cells.

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

#96
post #75
post #70

Question.. All my device lithium batteries seem to lose ~70% of their ability to hold charge after 500-1000 cycles, however the tesla car batteries/powerwall claim to give a decade+ of use despite being built of the same cells. How does that work?

I believe most of the physical damage done to a battery occurs either near 0 or 100% charge, and assume that automotive batteries are less frequently fully depleted.

They probably also never charge them up fully (have extra capacity wrt promised), at least when new.

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

#97
post #86

Earlier quoted context omitted.

Yeah but if you hack your Tesla even to change the color theme of the display, you'll probably loose warranty, loose certification status or whatever it is called (so you can't have any new parts installed unless it is expensively recertified), you'll get a call from Tesla asking what the hell you are doing, and so on. On the other hand, I can replace almost every part in my conventional car without ill effects from…

Not for long. You can still do this with older cars, but newer ones really restrict you. I just bought a new car and am not even allowed to jump start someone else's battery without risk of voiding my warranty.

In large part thanks to the CAN bus and how jump starting is likely to cause enough spiking to fry the boards.

Was trying to help a relative with some issue with their car the other day, and the wiring diagram for the part and related controls almost seemed to run in reverse depending on how the switch was set.

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

#98
I don't think the trouble of scavenging, testing and grouping the laptop batteries is worth it. The cheapest quality cells I've found costs around 210 euro for 1 kwh. To reach the same capacity you would need ~17 healthy laptop batteries @ 60wh.

With all the added work, buying just one type of cell seems way better. But really, why not buy deep cycle lead acids and an auto-watering system? No hype!

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

#99
post #80

Earlier quoted context omitted.

My annoyance with Tesla is somewhat related. I don't like that I can't simply buy a Powerwall or solar roof tiles. I would have to hire one of their approved installers, which increases the cost remarkably. I don't know the markup, because you can't get flat materials pricing data from Tesla, or couldn't last time I checked, but I know labor for solar installation and electrical work is quite high. I understand why t…

Imagine the bad PR you would get when your product kills your customers.

The other car manufacturers seem to cope, it's not particularly obvious why Tesla should be unique in that respect and why they need to lock everything down to such an extent.

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

#100
post #52

The original story is far better researched and more technical. Can we change the link to that instead of this repost? https://motherboard.vice.com/en_us/article/kzz7zm/diy-powerw...

You're right, this is way better!

A good place to start is here: http://diypowerwalls.com/
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