Amazon.com : UltraPro LI-50B Battery 2-Pack Bundle 1000mAh Digital Video Batteries with Rapid Travel Charger for Select Olympus Cameras Including SH-25MR, SP-720UZ, SP-800UZ, SP-810UZ, and SZ-31MR : Digital Camera Battery Chargers :
User manual Olympus SZ-31MR (English - 82 pages)
Amazon.com : Battery for Olympus SH-21, SH-25MR, SZ-20, SZ-30MR, SZ-31MR iHS Digital Camera : Electronics
Olympus SZ-31MR Review
Amazon.com : Battery for Olympus SH-21, SH-25MR, SZ-20, SZ-30MR, SZ-31MR iHS Digital Camera : Electronics
Battery 2-pack + Charger For Olympus Sz-10,sz-11,sz-12,sz-14,sz-15,sz-16 Ihs,sz-20,sz-30mr,sz-31mr,sh-21,sh-25mr Digital Camera - Digital Batteries - AliExpress