Battery Maximizer

[First Light]

The battery maximizer on my T42p reads 98%, sometimes 99% even after the computer has been on all day (I have only used the computer on battery once for a couple of hours). Shouldn't it read 100% after it has been on charge all day?

[Humpa]

The battery will not start charging until it is below the charging threshold (default is 95%). With the new T42's, you can now change this threshold. Right click on the battery icon in the taskbar and choose the 'improve battery health' option from the menu.

Here is some basic battery info from batteryuniversity:
http://www.batteryuniversity.com/parttwo-34.htm

Simple Guidelines

* Avoid frequent full discharges because this puts additional strain on the battery. Several partial discharges with frequent recharges are better for lithium-ion than one deep one. Recharging a partially charged lithium-ion does not cause harm because there is no memory. (In this respect, lithium-ion differs from nickel-based batteries.)
Short battery life in a laptop is mainly caused by heat rather than charge/discharge patterns.
* Although memory-free, apply a deliberate full discharge once every 30 charges to calibrate batteries with fuel gauge. Running down the battery in the equipment does this. If ignored, the fuel gauge will become increasingly less accurate. The battery life will not be affected.
* Keep the lithium-ion battery cool. Avoid a hot car. For prolonged storage, keep the battery at a 40% charge level.
* Consider removing the battery from a laptop when running on fixed power. (Some laptop manufacturers are concerned about dust and moisture accumulating inside the battery casing.)
* Avoid purchasing spare lithium-ion batteries for later use. Observe manufacturing date. Do not buy old stock, even if sold at clearance prices.

[kjarrett]

I can attest that on my T21, the main battery lasted a good 4 years with nearly constant AC use. The system would gradually lose power over a period of about 10 days (hibernating, not suspending or shutting down), hit the 95% threshold, and recharge. I only rarely would run the battery down to zero, just a few times per year usually. I was convinced that the charging process was working optimally to ensure the long life of my battery.

My T30 is, of course, another story ... it starts charging (hits 95%) after only two days or so after overnight hibernation. My gut instinct tells me this constant charging (many times more frequent than on my T21) isn't a good thing (and shouldn't be happening). Reference my other posts...

-kj-

[First Light]

Humper - I unplugged the A/C adapter, let the battery go to 93% and plugged the A/C adapter back in. Yup, back to 100% Thanks again.

Just posted another question that Kjarrett brought up about battery in or battery out.