Archive for December 20th, 2018

Dell Laptop Battery Teardown

The defunct 18650 lithium cellĀ  I used for the DSO150 power supplyprompted me to crack open a battery from a long-gone Dell laptop to see if any of its cells were in better condition:

Dell laptop battery - case cracking

Dell laptop battery – case cracking

Yup, gently crushing it in a vise splits the case enough to work the Designated Prydriver around the joint, a process considerably simplified by the knowledge the case isn’t going back together again.

Prying the top off reveals the cells and their connections:

Dell laptop battery - circuitry

Dell laptop battery – circuitry

One of the cells had corroded, accounting for the pack’s failure:

Dell laptop battery - corroded cell

Dell laptop battery – corroded cell

The others were undamaged, but had self-discharged down to about 1.5 V over the course of several years and refused to charge.

The moral may be to tear the pack apart as soon as it fails, a point always easier to recognize in retrospect.

So I taped the packs to prevent shorts and tossed them into the recycle box.