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Using Discarded Laptop Batteries To Power Lights
mrspoonsi sends news of an IBM study (PDF) which found that discarded laptop batteries could be used to power lights in areas where there's little or no electrical grid. Of the sample IBM tested, 70% of the used batteries were able to power an LED light for more than four hours every day throughout an entire year.
The concept was trialed in the Indian city of Bangalore this year. The adapted power packs are expected to prove popular with street vendors, who are not on the electric grid, as well as poor families living in slums. The IBM team created what they called an UrJar — a device that uses lithium-ion cells from the old batteries to power low-energy DC devices, such as a light. The researchers are aiming to help the approximately 400 million people in India who are off grid.
If you're discarding laptop batteries while they can still hold a charge
You are likely to discard the battery as soon as it can no longer hold a satisfactory capacity for your application. The battery is no longer effective for your use at that point, and you're wasting electricity time and $$$ and not getting the portability you want.
Based on the IBM study:
Sure, your laptop battery may not hold enough charge to power your laptop any more, but an LED needs a lot less power than your laptop, depending on what it's being used for. Most of the lightbulb-replacement LED bulbs I've seen want 9-23 watts, but the flashlights are more like 3w, and nightlights are more like 0.5 watts.
Also, that laptop battery is a battery of cells, and they usually don't all die at once. They may not be in good enough shape to remanufacture into new laptop batteries, but still have enough of them good enough to disassemble at third-world labor costs to recover cells for off-grid LED lighting.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
Do the communities who benefit from the secondary-use life of these batteries have the infrastructure and culture to properly recycle the materials; or will they end up in landfill/discarded into the environment?
So, these recycled batteries are being charged with what kind of charging controller, using what kind of input power?
If it's something creative like solar, I'd be very surprised if we don't get an impressive fire out of the first 100 unit-years of use...
Even if they have "grid power" to charge from, the charge controllers had better be good enough to sense a damaged cell, and when those sophisticated chargers refuse to charge the pack anymore, some genius level electrical engineer will hook up a "dumb" NiCad charger to the pack and get some more life out of it - the practice will spread and it won't be long before somebody sets the shanty town ablaze...
You are Exactly the person the grandparent post is talking about.
Here in Japan, we have current meters on a lot of electrical panels (Because you likely don't know: Japan is a major 1st world country, was #2 GDP until a year or so ago). Also, our electricity service is about 30 amps per residence. I have heat on when I need it, in the rooms I need it in (guess what... just like North America before about 1960s). I take the train to the office at 1/10th the cost, save the fuel/pollution and do email/read slashdot at the same time.
Guess what? My environmental footprint is about 1/5 of what is was in North America. And I consider my lifestyle is IMHO quite a bit better.
You've bought in to the corporate media message. USA (not North America now) is about 25% of the resource utilisation of the whole world. That is wasteful. I don't want to be a part of that, and so I do my part (see above, you wasteful POS). And not only that, but I work for a company that builds Electricity Grid monitor technology.
You? Keep being grateful that you can waste to everyone detriment... until you can't.
India is one of the countries where the US sends batteries to be recycled so it's almost certain that they are better at it than we are.
If not, we didn't care before when we sent them our batteries so why should caring about it be an issue now when it can get in the way of an improvement?
Was a real answer what you were looking for or was it just a petty flag waving exercise that makes us all look bad?
The problem with Lithium ion batteries is that their failure mode is often really obnoxious. When one cell in a pack fails, the battery ceases to be usable as a laptop battery, because as soon as you discharge down below some arbitrary fraction of its capacity, the voltage suddenly plummets below the operating threshold for your hardware, and the machine shuts itself off unceremoniously, with no opportunity to save your work or shut down cleanly. If the failure percentage is 5%, a few people will put up with it, and make a mental note not to let it get too low. If the battery drops dead at 60%, or if the failure point is a bit more variable, then you have to be pretty seriously hardcore to keep using the battery, because you risk losing all your data if you do.
However, under a lighter current draw, those same batteries will behave much better. The voltage probably won't sag at all, because (if I understand the problem correctly) there's enough time for the charge to properly redistribute itself across the entire pack even with a single, high-resistance (bad) cell. And even if it does sag, a voltage sag on an LED light would just make it put out less light, which isn't a big deal. For that matter, if they're cracking open the packs, they could probably fully utilize most of the cells for years before they would fail, so long as they toss the cells that have failed.
Check out my sci-fi/humor trilogy at PatriotsBooks.
Dude, I was soldering tabbed NiCD batteries into packs for my RC car when I was 12. Being afraid of small, low-voltage power sources because high-power sources could hurt you is like being afraid of house cats because lions and tigers can hurt you.
An incredibly useful amount of light can be provided by an LED headlamp for many, hours running on just a pair of AAA batteries. I hang it around camp all the time as a lantern providing indirect light, or more than enough direct light to read by. And that represents about 3Wh of capacity, versus the 60Wh for a smallish laptop battery. That small battery, reduced to only 10% of it's already meager original capacity, is not going to give you even remotely enough power for your laptop to be portable anymore, but would still provide twice the capacity of that headlamp. At 20% capacity you're probably overdue for a battery replacement if mobility is important to you, and that will give you 8 AAAs worth of power.
So we've got what, maybe $8 worth of decent quality NiMH-equivalnets right there, being thrown away as nicely packaged trash? If you can harness that trash stream to make solar lamps you could improve a lot of lives, while making sure those batteries get every last bit of life wrung out of them by people who know the value of a nickel.
I see two potential problems though - the first is pollution: we'd be interrupting a recycling-stream (one can hope) to re-purpose the batteries. We'd want to make sure they get back into that stream when fully dead. Hopefully there's large enough profit margins or subsidies in the system that people can make money buying dead batteries from people in the slums and villages to sell to the recycling plants, otherwise we have to trust to sufficient environmental awareness to keep these things out of the rubbish heaps.
The second is the fire hazard. I'm not certain how much, the fire hazard of a Li-ion battery increases when it's on its last legs, but distributing large quantities of low-individual-risk firebombs among the world's slums could be unfortunate.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
dgatwood may be over-paranoid, but Lithium Ion batteries aren't to be messed with unless you enjoy dealing with thermal runaway.
And it doesn't matter if someone else wastes something that isn't yours
Yes, it does matter.
In every 'dead' laptop battery I've torn down, one cell (or pair, in parallel) is totally kaput, and the remaining cells retain at least 50% of their nameplate capacity. Protection circuitry will lockout recharging of the whole pack, which wouldn't work with the dead cell anyway.
So the battery as a whole is utterly useless for the laptop, but 2/3rds of the cells or more have some life left in them, for other purposes.
I imagine a lot of the too-cheap-to-be-true off-label replacement laptop batteries are in fact combinations of two dead ones, with the remaining functioning cells rewired into one working (but lower capacity) pack. Certainly seems about right judging by the performance of them, anyway.
Sent from my PDP-11
I followed a thread on candlepowerforums about a guy who experienced permanent lung damage due to two mismatched lithium ion batteries in a flash light - one was presumably significantly in a different state of charge OR just a bad cell; experienced severe discharging and proceeded to thermal runaway in his house. In trying to get the light outside, he breathed in the toxic fumes and has permanent lung damage as a result. Be careful....
Karnal
Because this wasn't intended to be a practical solution to anything; it was a feel-good publicity stunt. As you say, a garden light with a built-in charger makes more sense.
"I wonder why they don't use car batteries instead?"
... because pretty much everything from a dead car battery can be recycled to make new car batteries and other stuff ...
The battery is broken apart in a hammer mill; a machine that hammers the battery into pieces. The broken battery pieces are then placed into a vat, where the lead and heavy materials fall to the bottom and the plastic floats. At this point, the polypropylene pieces are scooped away and the liquids are drawn off, leaving the plastic
Polypropylene pieces are washed, blown dry, and sent to a plastic recycler where the pieces are melted together into an almost liquid state. The molten plastic is put through an extruder that produces small plastic pellets of a uniform size. The pellets are sold to a manufacturer of battery cases and the process begins again.
Lead grids, lead oxide, and other lead parts are cleaned and heated within smelting furnaces. The molten melted lead is then poured into ingot molds. After a few minutes, the impurities float to the top of the still molten lead in the ingot molds. These impurities are scraped away and the ingots are left to cool. When the ingots are cool, they’re removed from the molds and sent to battery manufacturers, where they’re re-melted and used in the production of new batteries.
Old battery acid can be handled in two ways: 1) The acid is neutralized with an industrial compound similar to household baking soda. Neutralization turns the acid into water. The water is then treated, cleaned, tested in a waste water treatment plant to be sure it meets clean water standards. 2) The acid is processed and converted to sodium sulfate, an odorless white powder that’s used in laundry detergent, glass, and textile manufacturing.
"Transparent" is a shit show that trades on every stereotype going. A man in drag is NOT a transsexual.
The most common cause for laptop batteries failing is one cell has failed. Usually the one on the end of the battery that's closest to the CPU or otherwise hotter than the others.
The rest of the cells won't be that bad.