Battery charge suddenly drops from about 25% to 6%

I own a Lenovo Y500 series laptop. The battery being an year old lasts only 1 hour. But the strange thing is that, when the charge comes down to 25-20 it drops to 6%(critical battery level) in a moment.

Please suggest some solution (other than replacing the battery).

P.S. : I do many battery saving things already, like lowering brightness, switching to power-saver mode, turning off 'aero' on windows, etc.

Sorry to say it, but I don't think there's another answer to be had; what you are experiencing is usual for a battery that needs replacing.

Their expected life-span is only about 1 year (according to the manufacturers).

The reason the readings act weird is because when the battery becomes old and faulty it can't properly gauge the total capacity or current charge, so the gauge readings are based on inaccurate numbers.

There is some problem with the Lenovo Battery/UEFI Firmware. The Battery Manager on Window or tp_sampi module under linux is usually configured to extend the batteries life by only charging it to 85%.

But discharging the battery from 85% (eventually somehow related to hibernate) can cause the batteries charge counter to drift off more and more over time. The result is a sudden drop of battery life at some point (in my case, at around 45% it suddenly drops tp 6%). The battery reports 85% way too early.

People reported that setting the thresholds to 100% mostly resolved the problem after a few full charge cycles.