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> David McCay - Sustainable Energy without the Hot Air A fantastic book. A Caltech trained physicist at Cambridge does the calculations to see if the UK could get all its energy needs sustainably. Simple, easy to understand, and enlightening. It deserves the praise they talk about. And it's free to download.
If you like this, watch the videos from this guy: https://www.youtube.com/user/jehugarcia he methodically tests old 18650 laptop cells, sorts them, builds battery packs and so on. He's converted a classic VW bus to electric power using his home-made battery packs and packs salvaged from wrecked teslas.
> wrecked teslas Wait what? where is this supply at
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The key to batteries is being able to use the stored energy. Bonus points if you can add energy and get it back later.
Thermite :p
Yeah let's not use thermite to heat our houses people.
If you like this, watch the videos from this guy: https://www.youtube.com/user/jehugarcia he methodically tests old 18650 laptop cells, sorts them, builds battery packs and so on. He's converted a classic VW bus to electric power using his home-made battery packs and packs salvaged from wrecked teslas.
> wrecked teslas Wait what? where is this supply at
Given how popular (and damn near impossible to discern) unsafe and unprotected lithium-ion batteries are, the idea of making a homegrown power wall terrifies me in ways I can't even begin to contemplate. An 18650 battery, if combusted, can produce hydrofluoric acid with just water vapor in the air (or the water in your lungs) if they use lithium hexafluorophosphate as the electrolyte. Hydrofluoric acid can and will c…
I think your concerns are somewhat alarmist and tend to be a bit scaremongering. You may want to read an actual study about just how much HF is present in the fumes of burning cells. In this one, near the end they burned a whole laptop pack and analysed the gases that were emitted: http://www.brandforsk.se/MediaBinaryLoader.axd?MediaArchive_... The relevant datapoint is on page 61: "As seen the yields of HF is much l…
If that's happening due to a short (which can and does happen when a cell is charged improperly, or even put under resistive load after the cell is discharged below a safe limit -- copper or other ions, depending again on battery chemistry, can literally bridge across the electrolyte to short the cathode and anode) the result of the release of pressure combined with the reactive nature of now exposed lithium is a small rocket that shoots a plume of gasses like sulfur dioxide or hydrofluoric acid. Again, this depends largely on battery chemistry, and without an MSDS on these particular cells, there's no way to know. But there's a reason why any chemist you care to phone up will say, if you tell them you're in possession of a cylinder of a compressed compound that contains fluorine (it won't matter what kind, fluorine really really likes to bond promiscuously and with reckless abandon), they'll tell you that you're braver they are. Tell them you're intend to string up a few hundred of them and pass an electric current into them, and they'll call a hazmat team for you.
A casual stroll through forums frequented by flashlight fans (yeah, it's a thing) and you'll see plenty of demonstrations of what happens when a Li-ion cell begins a thermal runaway. And plenty of memorials to those who gave up their passion because they're on ventilators after experiencing profound damage to their lung tissues. Hell, ask the firefighters that respond to a fire at a battery recycling plant; granted, that's a bigger scale than one cell, but even one cell in a small room can, depending on its chemistry and how violently it's outgassing, emit enough HF to cause lung damage.
Read an MSDS yourself: http://www.uscg.mil/hq/cg4/cg432/docs/msds/MSDS_LiIon.pdf
LiPo "pouches" mentioned elsewhere in this thread are much less likely to explode spectacularly before bursting, and much less likely to exhaust a plume of corrosive, toxic chemicals in their wake.
Not related, but I hate this unit. Can't we just talk about Joules?
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You have to realize that 1kWh is a lot of energy. Imagine being hit (in a world without an atmosphere) by a 60 pound suitcase falling out of an airliner flying at 45,000 feet. Same amount of energy as that battery pack. (Alternatively: the most powerful air conditioner you can buy running full blast for 30 minutes. Incidentally, that battery pack has as much energy as 100mL of gasoline, which is why gasoline-powered…
Even a single AAA battery has a lot of energy 5,071 J according to http://www.allaboutbatteries.com/Energy-tables.html . My point of reference I use to imagine energy is a major league baseball player hits a baseball with 1,234 J. 1KW/h is 3,600,000 J.