NGM BL22 Fred Smartphone Compatible Battery 3.7V 1200mAh

NGM Fred — 3.7V Li-ion Replacement Battery (BL22)

This is a 3.7V, 1200mAh lithium-ion replacement for the BL22 cell fitted to the NGM Fred. It fits directly into the Fred's battery bay and connects to the same three-contact board the original BL22 uses. Capacity is 1200mAh — confirmed from product data, not estimated.

• NGM Fred battery bay fit: The Fred uses a slim removable cell at 60.00 × 43.80 × 4.50mm with a three-pin contact strip. This cell matches those exact dimensions and contact pitch, so the back cover seats flush without pressure on the contacts.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the bench. The BMS held the charge termination voltage correctly and did not trip on a standard 5V USB charge input. No thermal event was recorded during the charge phase.
• Fuel gauge recalibration on first cycle: On first use after installation, run one complete discharge down to automatic shutdown, then charge uninterrupted to 100% before use. This lets the Fred's fuel gauge IC map its percentage readings against the new cell's actual discharge curve rather than the old, degraded one.

Sudden shutdown at 20–30% on the NGM Fred after a cell swap

The Fred's fuel gauge IC stores a discharge model built from the old, degraded cell. A new cell has a steeper voltage curve near the bottom of charge, so the IC reads the voltage drop and triggers shutdown while the percentage counter still shows 20–30%. This is not a fault with the replacement cell — it is a calibration mismatch. One full discharge-to-shutdown followed by a full uninterrupted charge corrects the stored curve. After that cycle, the shutdown point returns to below 5%.

NGM Fred not powering on after the battery sat discharged in storage

Lithium-ion cells discharged below approximately 2.5V trigger a BMS protection lockout that blocks normal power-on. This happens when a phone sits unused for months with a depleted cell. Connect the Fred to a 5V USB charger and leave it for 20–30 minutes without pressing any buttons — the charge IC trickle-charges the cell back above the BMS threshold before resuming normal charging. If the charge indicator light does not appear within 40 minutes, check that the USB cable is delivering voltage with a different device before drawing other conclusions.