Sunday, May 19, 2013

Harvesting 18650 Cells From Old Laptop Batteries

Lithium-ion 18650 Cell, Harvested From HP Laptop Battery
Definitely Sony
I was reading somewhere that most laptop batteries use 18650 lithium-ion cells internally, and it hit me. I had a laptop sitting in a drawer that died shortly after I bought a brand new battery for it. The battery was about 4 years old, so I took it out and pried it apart. Inside the laptop battery case, as expected, were 12 green 18650 batteries. They are most likely Panasonic. Since the laptop died shortly after buying the battery, each of these cells probably only saw a couple charge cycles-they are almost new!

A quick reading on the multimeter showed that most of the cells were reading at least 3.5 volts. Not bad for sitting in a drawer for several years. The laptop manufacturers must subsidize these cells, because I have 12 cells that cost $10 each, and I know that the laptop battery didn't cost anywhere near that.

DISCLAIMER: Li-ion cells can be dangerous if handled wrong. Don't be a dumbass. I even sparked a couple of my cells because I was so impatient cutting them apart. I'm surprised natural selection hasn't claimed me already. If you have any doubts about what you are doing, stop, and visit the Battery University.

What I intend to do with these cells it to put them into a power pack as a backup/emergency charging system for my electronics. A good power pack costs close to 100 bucks and probably has cheaper cells inside than what I am putting in.

The only real downside is that they are welded together in the pack, and breaking them up leaves these little sharp burrs. I've seen it mentioned where some folks are using a Dremel tool to smooth them out, but I'll probably just use a small file.

Update: As pointed out by Chris below in the comments, these are definitely Sony 2400 mAh cells.

Gallery


12 Lithium-ion 18650 Cells, Harvested From HP Laptop
I had to cut the little plastic bars holding them in
12 Harvested Lithium-ion 18650 Cells, Partially Separated
Partially separated. Be careful cutting them out!

12 Harvested Lithium-ion 18650 Cells, Fully Separated
Fully separated, but each one has some burrs on it. Be careful not to cut yourself!

5 comments:

  1. . I do the same thing with old laptop and power tool packs. I always amaze myself with the uses for these. Flashlights,Portable cell phone chargers,Lasers,Radios,Motors,electric bike.

    You can peel those welded tabs with a pair of pliers and then solder them if you use a hot iron and are quick otherwise they can be damaged. I'm pretty sure those are Sony cells.

    If you don't have one already, get your self a good RC charger. I use a Icharger 106b definitely necessary for li ion cells.

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  2. Thanks for pointing out that they are Sony cells, Chris. This was definitely a good score. We also use lots of these 18650 cells. The wife is going to try one of these for her E-Ciggy as well. I've been smoothing them out with the Dremel tool, which was well worth the effort. Not bad for something that was headed to the trash.

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  3. This comment has been removed by the author.

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  4. Because a laptop is pretty compact, some of the recent technology that's been developed for desktops has yet to be made into thinner and smaller forms and successfully fitted into laptops. So laptops are always a step behind desktops when it comes to capability and efficiency. However, the laptop market is growing and this situation is fast changing.
    touch-screen-laptops

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  5. Hello Mark,
    This is an intelligent post. The post is informative and good post. Thank you for your nice sharing. Hope you post your next article soon.

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