{"product_id":"canon-c300-mark-i-replacement-battery-74v-6600mah-li-ion","title":"Canon BP-975 C300 Mark I Replacement Battery 7.4V 6600mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eCanon C300 Mark I \/ EOS C100 Series — 7.4V Li-ion Replacement Battery (BP-975)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThe BP-975 is a 7.4V, 6600mAh lithium-ion battery for Canon professional cinema cameras. It fits the C300 Mark I, EOS C100, EOS C100 Mark II, GL2, and 13 additional Canon models sharing the BP-975 form factor. Capacity is 48.84Wh — matched to the OEM specification.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eC300 Mark I and EOS C100 platform fit:\u003c\/strong\u003e\n    These cameras share the BP-975 battery slot, connector pinout, and BMS communication protocol. The voltage rail and cell count are identical across the platform, so one battery services multiple bodies on a mixed kit.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through charge and discharge cycles on a C300 Mark I body. The BMS handshake completed on first install, battery-remaining display updated correctly, and no authentication errors were logged during continuous recording.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-cycle initialisation on Canon cinema bodies:\u003c\/strong\u003e\n    On initial install, run one full charge cycle through the OEM Canon charger or the camera body itself before heavy production use. Some Canon BMS firmware maps the battery-remaining percentage by completing a reference cycle — skipping this step can cause erratic percentage readouts on the first shoot day.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the C300 Mark I draws harder than the rated spec suggests\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe C300 Mark I combines a Super 35 CMOS sensor, internal ND filter motor, dual recording paths, and continuous autofocus into a single power rail. Each system pulls current simultaneously during a take. That combined draw exceeds what a simple voltage and capacity rating predicts. A cell at 80% state of charge can show voltage sag under this combined load, which the BMS reads as a low-battery condition even when the displayed percentage still looks healthy.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBattery percentage jumping mid-shoot on the C300 Mark I\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens when the camera's BMS is mapping percentage thresholds against a discharge curve it has not yet fully calibrated to the new cell. The OEM firmware uses voltage-to-percentage lookup tables tuned during a reference cycle. A new cell without that reference cycle completed will show erratic jumps — typically dropping 20–30% suddenly, then stabilising. Run one full charge-to-discharge cycle and let the camera reach a resting voltage of approximately 7.0V before recharging to reset the calibration baseline.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43333787648090,"sku":"BWCS-BP975MC-1","price":51.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43333787680858,"sku":"BWCS-BP975MC-2","price":60.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43333787713626,"sku":"BWCS-BP975MC-3","price":66.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-BP975MC-1.webp?v=1778213126","url":"https:\/\/batteryweb.com\/products\/canon-c300-mark-i-replacement-battery-74v-6600mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}