Im using this V400 mouse and used a Energizer Rechargeable (2500mAh) and I found that the battery last upto 12days to be exact, is this normal? isnt its too fast for a rechargreable battery to last? Im using this for about 8 to 10 hours a day and I dont leave the USB dongle in my laptop.
If I use Energizer Alkaline Batteries, how long it will last to this mouse?
PLease advice.

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