01-06-2012 11:44 AM
I've seen this is a common trend going around, however I have not seen any fixes for it yet. On the e420s, I have had two main battery problems with respect to other owners.
The first is that the battery life is unbelievably short. I know that lenovo advertised 7 hours which means I should probably expect 4 or so when doing basic tasks -- I've seen many user and professional reviewers of the laptop post that they get 5 hours of battery when using 60% brightness and reloading webpages, even watching videos. However, I get approximately two hours of battery when everything is configured at the lowest settings --- brightness 0%, CPU on lowest, fan speed on passive, internet turned off, no java or any entertainment programs running - I get about 2 hours when the only program running is Word.
The next is a problem that started about a month ago. 4 or 5 times in the past month when running on battery power, the battery will shoot from about 45% to 6% instantly. It's always these two values specifically. It turns the 2 hours of battery into a little over 1.
Lenovo sent out the battery firmware update in October which I performed. In doing so, the battery life actually hit 4 and a half hours for a few days. I thought that that was the fix. But after less than a week later, the battery went back to normal. I tried reinstalling the firmware update but it did no good.