Restore reliable backup power to your garage door system with this premium replacement battery designed specifically for the LiftMaster 475LM EverCharge External Battery Backup Unit (BBU).

⚠️ Important: This listing is for the internal replacement battery only — not the full 475LM plastic backup unit housing.

Engineered for seamless compatibility, this 12V 4.5Ah sealed lead acid battery replaces OEM part number 41B591 and installs directly inside the 475LM EverCharge battery backup enclosure. It provides dependable standby power to keep your garage door opener operational during electrical outages.

When paired with compatible LiftMaster DC motor openers (including models 2500, 3500, 3550, 3800, and 8500), the EverCharge system can deliver up to 20 open/close cycles during a power failure — ensuring security and uninterrupted access to your garage.

Manufactured to OEM specifications, this maintenance-free SLA battery features a compact footprint for easy installation, integrated wiring harness, and consistent recharge performance through the existing 475LM charging system.

Ideal for replacing aging or failing batteries indicated by system beeping or red LED alerts, this battery helps maintain full functionality of your external backup power supply.

Backed by GarageDoorProject™, a trusted US-based garage door parts supplier, this battery is industry tested and supported with a 1-Year Replacement Warranty for peace of mind.

🔧 Technical Specs (Optional “Product Details” Section)

• Model: 41B591 Replacement Battery

• Voltage: 12V

• Capacity: 4.5Ah

• Battery Type: Sealed Lead Acid (SLA)

• Terminal: F1

• Dimensions: 3.54" x 2.76" x 3.98"

• Weight: 3.52 lbs

• Rechargeable: Yes