Do you have an old laptop whose battery struggles to reach 30 minutes? I used to.
An aftermarket 6-cell pack would have cost me around $40, which isn’t expensive, but the laptop was old (circa 2006) and not worth putting money into. I happened to have a fair number of Lithium-Ion battery cells “lying around”, and decided to upgrade my pack, not just with new cells, but with more cells.
This project was completed about a year ago, and I’m surprised I never posted it before!
I’ve always been a fan of rechargeable batteries because batteries, as a one-time-use product, simply don’t make sense. The ability to recharge the same batteries, hundreds of times, means less waste and more value for money. A downside to NiMH and NiCad batteries is that they output a lower voltage: 1.2V instead of the 1.5V provided by alkaline batteries, which can result in some devices displaying incorrect battery levels or shutting down too soon.
Another major downside is price, and shady marketing. Several years ago a 4 pack of rechargeable NiMH AAs, at 2500mAh, would cost about $12. It was a premium over alkaline batteries, but it was great value considering the many additional uses. However, these days I can’t seem to find the same type and capacity of batteries for under $17 at retail stores. Those batteries that are under $17 often do not have their capacity marked anywhere on the packaging or themselves. After some research, I discovered that these [brand withheld] batteries are only 1200mAh – less than half the standard for NiMH AAs.
It is unfortunate that a product that was once so economical and convenient was turned into nothing more than a cash grab. “Save the environment” slogans leading consumers to buy products at marked up prices. Supply and demand fails in this system. But I digress.
At the beginning of the semester, I turned on my calculator to find the “low battery” nag screen, followed by an immediate shut down. They were depleted. Being curious, and a little cheap, I decided to act upon an article I had read years ago. The article describes how, with patience and constant attention (if you wish to avoid acid explosions), you can recharge “non-rechargeable” alkaline batteries.
For every project I post on here where I obtain the results I was looking for, chances are there are two other projects I’ve tried that didn’t quite work out. Such is the nature of tinkering and hacking for fun.
Just because it ended in failure (and occasionally, catastrophic failure), it doesn’t mean I’ve wasted my time – here are some lessons I’ve learnt from failure over time.