Laptop Battery FAQ
Should I disconnect laptop battery when my notebook is AC adapter powered?
Many websites recommend to disconnect notebook battery when your laptop is AC powered because:
- It protects the notebook battery from the heat generated by the laptop.
- It protects the laptop battery from high voltage.
Although these are true, disconnecting laptop battery may not be necessary for many cases and can even cause issues because:
- As explained earlier, many laptop computer vendors provide utility programs that control the HP elitebook 8530w notebook battery charge level. This will eliminate the problem #2.
- In addition, laptop batteries are often located at the cool part of the notebook such as the backside (near the LCD panel hinges) of the laptop. In these designs, notebook battery temperature usually stays below 35℃ with normal use. If your laptop is designed this way, the problem #1 does not affect the laptop battery life.
And many laptops are designed to limit its performance (limit the maximum CPU clock frequency) when the battery is disconnected. This is because the Toshiba PA3468U-1ACA AC Adapter alone may not be able to sustain the battery power needed by the laptop at its maximum performance state.
Some laptop lower the CPU clock only when its power adapter cannot sustain the needed power (example in Figure 7), but some other laptop apply much more conservative policy and limit the CPU frequency to very low level while the laptop is powered by AC only (example in Figure 6).
If your laptop behaves this way, you may not want to disconnect battery so that you can get full performance of your laptop.
