BQ77915: BQ77915 Cannot Restart Charging After Undervoltage Cutoff - Need Wake-up Solution

Part Number: BQ77915

Hi TI Support Team,

I'm experiencing a critical issue with my battery management system design and need your guidance.

System Configuration:

• Topology: Solar Panel → BQ2460 (Charger IC) → BQ77915 (BMS IC) → 3S Li-ion Battery Pack
• Battery: 3S Li-ion configuration
• Charger: BQ2460
• BMS: BQ77915

Problem Description:

When the battery pack voltage drops to the undervoltage threshold, the BQ77915 correctly cuts off the output (DSG FET opens) to protect the cells. However, this creates a "chicken and egg" problem:

1. Battery voltage drops below UV threshold
2. BQ77915 opens the discharge FET (DSG)
3. BQ2460 charger cannot detect the battery pack (no voltage at charger input)
4. Without battery detection, BQ2460 cannot start charging
5. Battery remains disconnected and cannot be recharged

Question:

How can I implement an automatic wake-up or pre-charge circuit to allow the BQ2460 to restart charging after a UV fault condition?