Battery = Cell++

alt="This NiMH unit came from an IBM ThinkPad " align="left">Notebook

batteries are a law unto themselves. Like temperamental cats they decide when and what

they will do. You may be in the middle of the most important work of your life. But, so

what? Your notebook battery may decide that it’s time for a snooze. And there’s

nothing you can do about it if you are not near a power socket.

How much backup time does a battery give?

Like the heart of women, this too, is a dark, unfathomable secret. Mine sometimes gives a

half hour, and sometimes less than five minutes. And I have absolutely no way of guessing

how much I will get next time.

alt="No major secrets here too. The Compaq’s battery with its old NiCd cells"

align="left">Have you ever wondered what lies inside those

black boxes? What hidden circuitry makes them behave the way they do?

One lazy Saturday evening, having nothing

better to do, I decided to get inside a few notebook batteries. Here’s a visual tour. src="../images/BAT-1a.JPG" width="100" height="58"

alt="Toshiba inside! 8 ordinary-looking cells, some wiring to hold them together, and one little component…"

align="right">

First, let’s get together some

batteries.

Five minutes with a screwdriver, and the

secret is out.

What a let down! Those expensive batteries

just have ordinary-looking cells inside!

And what’s inside the Portege’s

Lithium-Ion? Li-ion batteries are rumored to have some impressive digital electronics

inside.

But I didn’t find out. Cracking open

any part of the boss’s new notebook is not my idea of career advancement. Not even on

a lazy Saturday evening.