Zepto 6024W - Battery behaviour

This has been raised previously in another thread, but I am concerned by the steadily diminishing capacity of the battery in my Zepto 6024W.

According to the label, the battery capacity is 10.8V, 4800mAH which is 51,84mWH. This isn't a generous capacity to start with, considering that many notebook batteries are rated at either 11.1V and/or 5200mAH, but I would consider this acceptable if the battery maintained the stated capacity.

However, it has never had the original capacity. The first time I checked (5th August - after about 2 weeks) the capacity is reported as 47,315mWH. Today morning it was down to 44,464mWH. After a deep discharge and recharge I have raised it to 44,701mWH which is about 86% of the rated capacity.

I found a fix elsewhere in these forums which sets the critical battery action to do nothing and thereby allowing a full discharge. This is the command:

powercfg -setdcvalueindex SCHEME_CURRENT SUB_BATTERY BATACTIONCRIT 0

However, one of the battery problems is that 0% charge is not empty. The battery gauge reported 0% but it was actually 0.2% and stayed at 0.2% for about 9 minutes with a discharge rate of about 21W. That means just over 3,000mWH of capacity remaining when the battery says it is empty. Combined with Vista wanting to shut down or hibernate when the battery reaches 3% (and I think it actually means drops below 4%) then that's at least 15 minutes lost running time.

My conclusions: (i) The BIOS is frequently changing the nominal battery capacity during normal use. Many BIOSes contain a special routine for battery calibration but I have not seen this feature in the 6024W BIOS. (ii) When the BIOS is calibrating the battery, it seems to be misreading the zero and leaving at least 3000mWH of effectively unusable capacity below zero.

My complaint: The capacity has never been what it says on the label and seems to be decreasing too quickly. A loss of 25% capacity in a year is reasonable, but nearly 15% in just over 2 months is not.

Can someone in Zepto please comment?

John

 

have you tried to have it unplugged, discharge totally, then start it up, shut down, start up until it doesnt start anymore?

btw, I noticed a nice thing too a few days ago:
100.2% remaining

 

The command:

powercfg -setdcvalueindex SCHEME_CURRENT SUB_BATTERY BATACTIONCRIT 0

sets "do nothing" as the critical battery action and runs the computer until the battery is dead. That's why I know it will run for about 9 minutes with the gauge on zero. However, this isn't a safe way to operate under normal conditions. What I want is a properly calibrated battery and gauge.

John