Amazon.com: Synergy Digital Camera Battery, Works with Nikon Coolpix S3700 Digital Camera, (Li-Ion, 3.7V, 1000 mAh) Ultra Hi-Capacity, Compatible with Nikon EN-EL19 Battery : Electronics
En-el19 Battery (2) + Charger For Nikon Coolpix W100, A100, A300, S3600, S3700, S5200, S5300, S6800, S6900, S7000 Digital Camera - Digital Batteries - AliExpress
Nikon COOLPIX S3700 | Digital Point & Shoot Compact Camera