{"product_id":"ibaby-q9-replacement-battery-37v-900mah-li-ion","title":"iBaby Q9 Replacement Battery 3.7V 900mAh Li-ion","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eiBaby Q9 \/ Q9Ⅱ \/ Q9M — 3.7V Li-ion Replacement Battery\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 900mAh (3.33Wh) lithium-ion cell for the iBaby Q9, Q9Ⅱ, and Q9M baby monitors. It replaces the original cell when the device no longer holds charge or fails to power on. Physical dimensions are 46.20 × 34.14 × 5.68mm — confirm these against your existing cell before installation.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eQ9, Q9Ⅱ, and Q9M compatibility:\u003c\/strong\u003e\n    All three models share the same 3.7V cell footprint and connector pinout, so one cell fits the full Q9 line. The BMS handshake across these variants is identical — no firmware or hardware changes between units affect cell acceptance.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through charge and discharge on the Q9 platform. The protection circuit triggered correctly at low-voltage cutoff, and charge acceptance from zero was clean with no false-full termination on the first cycle.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration after swap:\u003c\/strong\u003e\n    On first use after installation, disable fast charging if your Q9 variant supports it, then run one complete discharge-to-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before it reports percentage to the monitor's firmware.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the Q9 monitor shuts down suddenly at 20–30% battery remaining\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens when the cell voltage drops below the point the device's processor needs to stay awake — even though the fuel gauge still shows charge remaining. A worn or new uncalibrated cell can hit this voltage cliff faster than the gauge predicts, especially under Wi-Fi transmission load on the Q9's live-streaming circuit. The BMS trips the cutoff before the OS can log a low-battery warning. One full discharge-charge cycle after fitting the new cell closes the gap between real cell voltage and what the gauge reports.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBattery percentage jumping or reading 0% immediately after installation\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe Q9 uses a fuel gauge IC that stores a charge curve calibrated to the original cell. A new cell has a different internal impedance profile, so the IC misreads state-of-charge and displays erratic or near-zero percentages on startup. This is not a faulty cell. Charge the unit to 100%, let it discharge to automatic shutdown, then charge back to full without interruption — after that single cycle the IC recalibrates to the new cell and percentage readings stabilise. If the device still shows 0% after a full cycle, check that the cell connector is fully seated.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43405109657690,"sku":"BWCS-NK5BHL-1","price":22.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43405109690458,"sku":"BWCS-NK5BHL-2","price":25.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43405109723226,"sku":"BWCS-NK5BHL-3","price":27.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-NK5BHL-1.webp?v=1779369992","url":"https:\/\/batteryweb.com\/products\/ibaby-q9-replacement-battery-37v-900mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}