Monday, May 11, 2009

How to charge and discharge laptop batteries to extend their lifetime Part 2

This is the second part of how improve the life of laptop battery by Michael Pietroforte

A laptop battery can be charged 300-1000 times. The actual number depends on the way it has been treated. In the last part the influence that the temperature has on a battery’s lifespan was discussed. This article highlights how a battery should be charged and discharged with care.

Fully discharge a new battery and then re-charge it. This calibrates the battery.

Calibrate the battery every 30 charges, i.e., fully discharge it and charge afterwards.

Avoid frequent full discharges. In contrast to NiCd (Nickel-cadmium) and NiMh (Nickel-metal hydride) batteries, Li-ion (Lithium-ion) batteries show no memory effect. That is, it will do no harm to the battery if it is re-charged before it is empty. Full discharges will strain the battery.

Avoid total discharges. Total discharges, i.e., to the cut-off point, can destroy battery cells. Not all cells in a laptop have the same voltage. Your laptop’s battery gauge only displays the state of the whole battery. If a cell goes below a certain voltage it will be destroyed. Therefore, it is safer to stop working when your battery level reaches 20%. The low battery level can be configured under Vista in the advanced power settings applet. Vista will warn you when the battery reaches the low battery level.

The orginial post can be found at:

http://4sysops.com/archives/how-to-charge-and-discharge-laptop-batteries-to-extend-their-lifetime/

How to take care of your laptop battery to prolong its lifespan

This was an article on 4sysops by Michael Pietroforte on how to increase the life of laptop battery. A good piece of article.

When I bought a new notebook recently, I resolved to take better care of my laptop battery this time than I had with my previous ones. With my last laptops the battery was more or less dead after a year or so. If a battery is treated with care it can last up to four years. I thought that I knew how a notebook battery has to be handled, but after googling this topic, I realized that quite a few of my beliefs were outdated. Most of my layman’s knowledge about rechargeable batteries was related to Nickel-metal hydride (NiMH) and nickel-cadmium (NiCd) batteries, which are no longer used in laptops (as far as I know). In this post, I summarize the tips I found on the web to preserve lithium-ion (Li-ion) batteries, which are probably in most laptops nowadays.

There are two important keywords when it comes to battery preservation: charging and temperature. That is, how the batteries are charged, and the temperatures to which they are exposed, are key factors that determine their lifespan. Today I will write about how temperature influences the lifespan of a laptop battery, and in my next post I will cover charging and discharging.

Many people believe that low temperatures are harmful for batteries because they think of past winters when their car didn’t start in the morning after a cold night. However, the technology used in car batteries has little to do with Li-ion batteries. The same applies to non-rechargeable batteries, which can even be recharged a little by exposing them to the warm sunlight. The truth about Li-ion batteries is that high temperatures are their worst enemy. Therefore, the following tips will help prevent laptop batteries from getting too warm.