See enV Touch batteries available for sale below
The LG enV Touch battery is a 950mAh Lithium-Polymer battery and with a manufacturer rating of 4.33 hours of talk time and 408 hours, or 17 days, of standby time. Many users report (in this forum post) having to recharge the phone every one or two days with normal usage.
Many users choose to buy an extra battery or spare battery for their enV Touch in order to ensure that they don’t lose use of their phone while on the road or at a crucial moment. Some users need to purchase a replacement battery in case of an unfortunate battery failure. For either of these cases, you can find either an official LG-manufactured battery or a third-party aftermarket enV Touch battery.
Buying an enV Touch battery from Amazon through the link below will help support enVTouch.org, the enV Touch User Community, with a small commission. Check out our community forums at enVTouch.org for the latest in enV Touch disscussion.

LG enV Touch VX11000 950mAh Standard Battery – Original (OEM) SBPP0027201
This is the very same battery that comes with the phone, manufactured by LG — with their 1 year warranty included.