Holux GPSlim236 Replacement Battery 3.7V 1000mAh HXE-W01

Holux GPSlim236 / GR236 / M1000 Series — 3.7V Li-ion Replacement Battery (HXE-W01)

This 3.7V 1000mAh Li-ion cell replaces the HXE-W01 battery in the Holux GPSlim236, GR236, M1000, and M1000B portable GPS receivers. It matches the original cell's dimensions (52.96 × 33.64 × 5.15mm) and voltage rail, so the unit powers on and charges without modification. Capacity is 1000mAh — identical to the factory specification.

• GPSlim236, GR236, and M1000 series fit: These four models share the same battery bay dimensions, 3.7V single-cell architecture, and HXE-W01 part number. Swapping between them requires no adapter or wiring change — the cell seats and contacts directly.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a GPSlim236 unit. The BMS accepted charge from the device's internal circuit without fault flags, and the low-voltage cutoff triggered cleanly before cell damage could occur.
• First-fix cold start after swap: After fitting this cell, power the GPSlim236 on outdoors in open sky and let it run. The unit performs a cold start after any full power interruption — first satellite acquisition takes 5–10 minutes. Subsequent warm starts drop to under a minute once almanac data is rebuilt.

GPS accuracy dropping at low battery on the GPSlim236

When cell voltage falls below roughly 3.5V, some GPSlim236 units reduce RF receiver sensitivity to cut power draw. The GPS still shows a fix, but positional error increases — sometimes by 15–20 metres in practice. This isn't a firmware bug; it's the receiver pulling back intentionally. Keeping the cell above 3.6V during active navigation prevents the sensitivity reduction from engaging.

GPSlim236 shutting off without a low-battery warning

The on-screen battery indicator on the GPSlim236 reads estimated charge, not real-time cell voltage. As lithium-ion cells age, their voltage curve flattens and then drops sharply — the indicator shows one bar and then the unit cuts out before any warning appears. A fresh HXE-W01 cell restores the sharper voltage curve, giving the indicator enough signal time to warn before cutoff. After fitting the new cell, run one full charge cycle so the device can recalibrate its voltage-to-indicator mapping.