My sister sent my mother an LG Optimus cell phone.

The instructions say:

Install the Battery
1. Remove the battery compartment cover ...

There are no diagrams of how to remove the battery compartment cover.

There is a manual for the LG Optimus here, but still no instructions for removing the back cover.

http://docs.google.com/viewer?url=http://www.lg.com/us/mobile-phones/pdf/VM670_MANUAL_ENG_1.0_FINAL.pdf

One thing I have learned with well engineered equipment is do not force anything, because if you do, you will break something you wished you did not break.

When you find the clever way the engineers designed how to take apart the equipment, it will part easily without the need for any but a slight force.

The battery compart cover is on the back of the LG Optimus, which is the other side from the viewing screen and the side with the camera lens.

Hold the LG Optimus in your hand, with the back facing you and the camera lens at the top.

Above the camera lens, as the cover curves over the top edge, you will find a small indentation.

Slip your finger nail in the indentation. Run your finger nail in the seem between the cover and the base, to your left around the corner and down the left side of the LG Optimus.

There are three little clips on the left side compartment cover that hold the cover to the base of the phone. When you run your finger nail along the seem, and let the cover stretch a little bit. The clips will release and you will be able to remove the cover.

When you put the cover back on, hold the cell phone the same way, with the back towards you and the camera lens towards the top.

Slip the cover on from your right to your left, fixing the right side in place and easily snapping the left side closed.