best rom for battery life ?

[scruff]

Hi,

My Vox begins to have some battery's problems (2 years old)...
I am no more able to send a sms if i have less than 50% battery left, it just shut down when i press "send"! Same probleme when i receive a call.
I tried different 6.1 and 6.5 roms with no better results, now i am hesitating to run a 6.0 windows mobile rom, do you think it could be better ?

Thanks.

[tobbbie]

This is a dead battery - any GSM related activity demands a lot of impulse-current drain which an aged battery cannot deliver well. For any other operation (even WLAN or BT) the battery will perform well. Different ROMs will not help you here. Maybe you try to clean the battery contacts and those of the device (e.g. with medical alcohol).
To optimize charging adjustment you may want to run down the battery completely by leaving it in boot-loader until shutdown (may take a few hours). Then charge it to 100% again - but while switched off. This ensures that the on-device (not SW driven) battery loading is re-adjusted.
Problem with batteries is that nowadays you will also get aged (despite not used) ones in shops. Most of those will not perform much better, sadly - due to LiIon chemistry. Look up some LiIon battery related threads around the net.