About this replacement
Thorn Voyager Blade 2 — 3.6V Ni-CD Replacement Battery (59011291)
This 3.6V, 2000mAh Ni-CD cell replaces part number 59011291 in the Thorn Voyager Blade 2 emergency lighting unit. It fits the Blade 2, Blade 2 E3D, 96633305, and 96633308 fittings. The cell powers the backup lighting system that activates on mains failure.
- Blade 2 and Blade 2 E3D compatibility: These fittings share the same 3.6V charge rail, connector pinout, and physical envelope — 67.70 × 44.60 × 22.70mm. The charge controller communicates with a single-cell NiCd stack, so voltage and chemistry must match exactly. Substituting a different chemistry will cause the charge controller to overcharge or undercharge the cell.
- Bench tested on actual hardware: We ran this cell through a full charge cycle and a timed discharge on the Blade 2 charge board. The cell accepted float charge within the controller's acceptance window and held voltage under load through the full rated period without the charge board tripping a fault condition.
- First-cycle commissioning tip: Hold the test button for the full rated duration within 24 hours of installation. This forces a complete load cycle, allowing the charge controller to register the new cell's capacity before it logs the next scheduled compliance test. Skipping this step can cause the fitting to record a failed duration on its first automatic test.
Emergency light failing its duration test after battery replacement
A freshly installed NiCd cell ships in a partially discharged state from storage. The Blade 2 charge controller begins a slow trickle charge on installation, but it takes 24 hours to reach full capacity from a storage state of charge. If the fitting runs an automatic duration test before that charge cycle completes, the cell cannot sustain output voltage for the full rated period and the test logs a failure. Run a manual test cycle after the first full 24-hour charge — the cell should hold above 3.0V under load through the complete duration.
Charge indicator staying red after new battery installation
The Blade 2 charge controller monitors incoming cell voltage before switching from fast charge to float. A cell sitting in storage can drop below the controller's float acceptance threshold — typically below 3.2V — which keeps the charge indicator in a fault or charging state. This is not a faulty cell; it is the controller working correctly. Leave the fitting on mains power for a full 24-hour period and the indicator should shift to green once the cell voltage rises into the acceptance window above 3.4V.