{"product_id":"olympus-e-m1-mark-ii-replacement-battery-74v-2250mah-li-ion","title":"Olympus BLH-1 Mirrorless Camera Replacement Battery 7.4V 2250mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eOlympus E-M1 Mark II — 7.4V Li-ion Replacement Battery (BLH-1)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 7.4V, 2250mAh Li-ion replacement for the Olympus BLH-1 battery. It fits the Olympus OM-D E-M1 Mark II mirrorless camera. The cell powers the sensor, autofocus system, and electronic viewfinder through the same voltage rail as the original.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eE-M1 Mark II compatibility:\u003c\/strong\u003e\n    The E-M1 Mark II uses a single BLH-1 cell on a 7.4V rail with a BMS handshake for battery-remaining display. This cell matches that voltage and the connector pinout. The BMS reads state-of-charge from the cell's discharge curve — a mismatch here causes erratic percentage readouts.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through the E-M1 Mark II body and an OEM HLD-9 grip. The BMS accepted the cell without error flags, and cutoff triggered correctly at low-voltage threshold rather than throwing a false-empty warning mid-shoot.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst charge on the E-M1 Mark II:\u003c\/strong\u003e\n    Complete the first full charge cycle inside the camera body or OEM BCH-1 charger — not a third-party USB charger. The E-M1 Mark II BMS maps its battery-remaining indicator against an internal calibration cycle. Skipping this step often causes the percentage display to jump or read inaccurately from the start.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the E-M1 Mark II shot count drops under sustained 4K or continuous AF\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe E-M1 Mark II pulls current from four major draws simultaneously during video or burst shooting: the sensor, the image processor, the 5-axis in-body stabilisation, and the phase-detect AF system. Combined draw during 4K recording is significantly higher than during single-shot stills. The rated shot count is measured under CIPA conditions — mostly single-frame stills with the EVF off — not continuous recording. Switching to a smaller JPEG format or reducing AF sensitivity in the menu will lower current draw and extend each charge.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBattery percentage jumping on the E-M1 Mark II display after fitting a new cell\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe E-M1 Mark II maps its battery-remaining percentage against a stored discharge-curve profile from the BMS calibration cycle. A new, uncalibrated cell has a slightly different resting voltage at each state-of-charge point, so the camera misreads percentage at certain thresholds. This is not a faulty cell — it is a calibration gap. Run one full discharge down to camera cutoff, then charge to 100% inside the camera body or BCH-1 charger. After that cycle, the percentage display stabilises.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43333639667802,"sku":"BWCS-BLH1MH-1","price":43.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43333639700570,"sku":"BWCS-BLH1MH-2","price":50.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43333639733338,"sku":"BWCS-BLH1MH-3","price":55.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-BLH1MH-1.webp?v=1778213018","url":"https:\/\/batteryweb.com\/products\/olympus-e-m1-mark-ii-replacement-battery-74v-2250mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}