Bamboo CTH-470K Stylus Replacement Battery 3.7V 1200mAh

Bamboo CTH-470K-xx Series — 3.7V Li-ion Replacement Battery (1UF553450Z-WCM)

This 3.7V, 1200mAh Li-ion cell replaces the internal battery in the Bamboo wireless stylus used with CTH-470K-xx pen tablet models. It fits the CTH-470K-DE, CTH-470K-EN, CTH-470K-FR, and over 20 additional regional variants in the CTH-470K line. When the original cell no longer holds a charge, this swap restores full wireless pen operation.

• CTH-470K variant coverage: All CTH-470K-xx models use the same stylus housing, connector footprint, and BMS handshake protocol — the regional suffixes reflect keyboard bundle or locale differences, not battery architecture. One cell covers the full range.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the CTH-470K stylus. The BMS accepted the cell without faulting, charge termination triggered correctly at full capacity, and pressure sensitivity resumed at normal operating voltage.
• Post-swap fuel gauge reset: After installing this cell, run the stylus down to automatic power-off, then charge it uninterrupted to 100%. The stylus fuel gauge IC was calibrated against the old cell — one full cycle resets it against the new cell and clears any erratic percentage readings that appear immediately after the swap.

Why the CTH-470K stylus shows full charge but dies mid-session

The stylus fuel gauge IC stores calibration data tied to the original cell's discharge curve. A new cell has a slightly different internal resistance profile, so the IC miscalculates remaining capacity and reports 100% well past the actual charge state. The pen cuts out not because the battery is faulty — it's because the gauge never saw the new cell's true floor voltage. One complete discharge-to-shutoff followed by an uninterrupted full charge teaches the IC the correct reference points.

Stylus not pairing after battery replacement

If the stylus fails to pair with the tablet after the swap, the pen's microcontroller may not have completed its boot sequence due to residual low voltage on the new cell. Remove the battery, wait 30 seconds to allow the capacitors to drain, then reinstall and charge to at least 3.9V before attempting to pair. If the tablet still does not recognise the pen, hold the stylus button for 10 seconds to force a full controller reset before re-pairing.