A Philosopher's Blog

Freezing Laptop Batteries

Posted in Technology by Michael LaBossiere on February 23, 2008

I have some modest amount of nerdastic powers when it comes to technology, so people often ask me to solve their computer problems. In return, people often dump truly broken hardware on me. Not in the sense of “dropping it on me with the intent of harm”; but rather in the same sense that a person drops junk off at the dump.

Fortunately, I hate to let things go to waste and I love a repair challenge. One recent challenge involved a 1998 Compaq laptop my ex-wife had “beaten to death.” The power supply was dead, the battery was dead and the case was cracked and broken in many places.

Replacing a laptop power supply is fairly easy-numerous companies sell “universal” replacements that come with a variety of tips. I use a Targus adapter that has served me well with a number of rescued laptops.

Fixing a cracked and damaged case is also easy. As long as the damage does not affect the safe operation of the machine, some glue and electrical tape will fix most cosmetic damage. Electrical tape also matches the black of many laptops quite closely.

The battery is a tough part. I had heard that freezing a battery can restore it. Since the laptop battery was dead, I figured it was suitable for an experiment.

The battery itself is a 1998 NI-MH battery for a Compaq 1275 Presario laptop. I took the battery and placed it within a ziplock bag. The bag is important to keep moisture off the battery and to otherwise protect it from what might be in the freezer (like leaking ice-cream).

I froze the battery for 24 hours and then removed it from the freezer. Since the battery was cold, I kept it in the bag to protect it from condensation. I then waited for the battery to warm up. After checking it for damage and wiping it down, I put it in the laptop and let it charge up.

Initially, the battery would take a charge but would discharge in a matter of seconds. The software also failed to recognize the batter. Then I charged the battery for a long time (several hours) and the software recognized the battery and it held a charge. Naturally, the battery is not as good as new and my trust in it’s staying power is quite limited. However, it does work again.

I tried the same technique with a Lithium Ion battery for a a Gateway laptop my ex-wife had also beaten to death. No luck with that. It might be the difference in the battery or it might be that the abuse inflicted on the Gateway damaged the charging mechanism (the titanium case was broken in some places). I did manage to repair its power supply to some degree. The Solo 3350 has a weird connector that apparently was only used in that model and hence my Targus adapter is of no use. It works reasonably well, but the battery is kaput.

So, freezing laptop batteries can return them from the dead. Before you freeze your batteries, I’d suggest only using ones that are already dead. Freezing a battery that is in decent shape might not help it and might actually do it some harm.