Laptop Recalibration As a laptop gets older, it starts to slow down a little. You may notice that pages load slower, videos take longer to start playing, and general slowness of the machine. Unfortunately, thousands of people a year replace their laptop batteries without performing any monthly recalibration on it at all. If you want to get the best performance out of your laptop, here are a few steps to follow. - Charge your laptop's battery all the way to 100%. -Once the laptop is fully charged, unplug it and let the battery drain. Feel free to use the laptop during this period, as it will help it drain more quickly. Once you see that the battery is almost empty, save your work and close any open pages. Then let the laptop shut itself off. -Let the dead battery sit for about 5 or 6 hours, or overnight. This will help eliminate any leftover charge the battery may have, and lets the battery start over from zero. -After you've let your laptop sit, plug it back in and let it charge all the way to 100% before using it again. Battery maintenance is an important process that many people neglect. Recalibration should be done monthly if possible to ensure best results. If done on a regular basis, you should notice greatly extended battery life on your computer, and hopefully postpone the purchase of any replacement parts.

A risk with third party batteries is that they not-infrequently are lower quality and have less capacity than OEM versions. I personally never take the chance. A dead battery in a laptop is like a needed major repair on a car - you go the cheaper route if the rest still works fine, or it's a good excuse to buy a whole new replacement. But even when going the cheaper route and getting a replacement battery, i think it's a false economy to buy an aftermarket brand. Capacity is rated in milliAmp hours, for laptops it's usually a number in the single digit thousands ( 3000-9999 mAh hours)

The provided link address far more than my question, rather the claim in PC Magazine. The claim is the battery will live longer if you remove it when A/C is connected. There is nothing here about how much energy is consumed, simply the constant charging of a battery when the computer is on A/C for long periods of time take life/longevity out of the battery compared to the case where the battery is sitting disconnected during these long periods of time with only it leakage current for a load. The article also recommends not running the battery down as compared to recharging it as soon, in the discharge cycle, as possible.

In numerous cases, Dell in particular, if you flip over the laptop there is a pushbutton on the battery and a series of LEDs that light up to indicate the level of charge when you push the button (assumes the charge circuit is operational and that the battery can hold a charge). I would start by checking Dell's website to see if the battery is part of any recall, many were. If you rarely use it on battery I wouldn't spend any extra on a larger capacity one. Third party ones should be used with caution, quality is often lacking. Personally I have used Lenmar replacements, for laptops and camcorders, when competitively priced. So far I have been lucky, some reviewers seem to diss them. I would definitely factor in the cost of a new battery vs purchase of a new warrantied unit also.