Batteries are an essential extra when you buy a digital camera, and while you can survive with just one, having a backup is always a good idea.
However, look online, and as well as Sony’s own brand batteries, there are countless aftermarket options. The Berenstargh NP-FZ100 is one example and sits at the upper end regarding price and quality.
The battery is designed as a direct replacement for the Sony NP-FZ100 batteries and has similar specifications. However, while both batteries offer the required 7.2V when it comes to the mAh and Wh, the specifications are slightly different. The Sony comes in at 16.4Wh and 2280mAh whereas the Berenstargh is rated at 14.7Wh and 2040mAh, that’s about 30% less in real terms.