Xiaomi BM4J Original-Capacity Replacement Battery (4500mAh)

The BM4J is a high-density internal Lithium-ion Polymer replacement battery manufactured specifically for Xiaomi’s highly successful gaming and performance-oriented mid-ranger, the Redmi Note 8 Pro. Because this smartphone runs a powerful MediaTek Helio G90T gaming chipset that draws significant power under heavy loads, a degraded or aging factory cell will show noticeable failure signs. These typically include the device overheating excessively during routine scrolling, dropping chunks of battery life instantly under 30%, or getting stuck in a continuous loop on the “Redmi” or “MIUI” startup splash screen. Swapping in a premium BM4J cell completely stabilizes power delivery and restores your phone’s native standby backup.

• Battery Model: BM4J

• Battery Type: Lithium-ion Polymer (Li-Po)

• True Capacity: 4500 mAh (Typical) / 4400 mAh (Rated)

• Standard Voltage: 3.85V

• Charging Voltage Limit: 4.4V

• Fast Charge Support: Fully calibrated to sync natively with Xiaomi’s 18W fast-charging standard without overheating or safe temperature overshoots.

• Safety Layout: Programmed with an original-grade double-IC Protection Circuit Board (PCB). This chip actively shields the phone’s mainboard against dangerous high-voltage spikes, prevents chemical bloating caused by overnight charging overloads, and feeds accurate real-time percentage syncing to the MIUI/HyperOS software.

• Device Compatibility: This exact 4500mAh structural profile and flex ribbon connector layout precisely match:

  • Xiaomi Redmi Note 8 Pro (