While we were away on a family vacation recently, our son Matthew, a member of the IT department at Brandeis, admonished me for allowing my laptop battery to run down. “Today’s lithium batteries don’t need and shouldn’t be allowed to run down and lose their charge, Dad…..”
He said these words with just the right amount of distain a computer genius (one that I created, mind you) could project. He quoted Steve Gibson, one of his favorite podcast resources and then sent me a YouTube link which you’ll find at the end of this article.
The reason so many people attempt to run their batteries down is to prevent a common problem prevalent in NiCad and Nickel Metal Hydride batteries called the “memory effect”. Originally, the terms memory effect or memory problem was coined to describe a cyclic memory problem where the NiCad battery would “remember” the amount of discharge for previous discharges and limit the recharge life of the battery. This memory effect would actually shorten the usable time you would get from the battery when the device was left plugged in all the time or recharged without first discharging the remaining charge. That’s the reason so many of us continue to follow the old logic of discharging and recharging these batteries regularly to help improve their usable life.
How to prolong the life of lithium-ion batteries.
There’s actually fail-safe circuitry in each cell of the battery that’s designed to prevent the battery from over-charging as well as over discharging. So it’s easy to prolong battery life by avoiding discharge and instead charge more often between uses. The smaller the depth of discharge, the longer the battery will last.
It’s still NOT recommended to leave a laptop plugged into a charger all the time. Battery life and usage is greatly enhanced when you allow the battery to go from 100% charged down to about 80% and then recharge. If you have a laptop, check the documentation that came with it or the company website to see what type of battery you have then follow the manufacturer’s care instructions.
For devices like the Kindle, iPhone, iPod, iPad and other Smart Phones with batteries that are not removable or end user serviceable, you should recharge regularly and not let the device run completely out of juice to maximize battery life.
See Steve Gibson’s podcast here:
http://www.youtube.com/watch?v=nqFr4Nd-9fQ
