The FZ53 specifications state you can take approximately 200 full resolution photos on a single, full battery charge. This number of photos does depend on how you use the camera, how many times you power it on/off, zoom in/out, etc. A lot of times you will get way more than 200, it really depends on the use.
We recommend you charge your brand new Li-ion battery for a minimum of 4-hours the first time you plan to use it.