Unican 502238 Electronic Lock Replacement Battery 9V 2700mAh

Unican 502238 Series — 9V Alkaline Replacement Battery

This is a 9V alkaline battery rated at 2700mAh (24.3Wh), built to restore power to Unican electronic door locks. It fits the 502238, 5022501070, 52238, and 700 series models, along with three additional variants in the same family. When the lock's battery dies, access control stops — this gets it back online.

• 502238 series compatibility: These Unican models share a common 9V power rail and battery compartment footprint. The lock's control board draws from a single 9V cell — same voltage requirement, same connector orientation, same physical cavity across the listed variants.
• Bench tested on actual hardware: We ran this cell through Unican lock activation cycles. The battery held voltage under the motor draw during deadbolt throw and maintained stable output through the keypad polling circuit without sag or dropout.
• Post-swap access verification: After fitting a new battery, test every access method — keypad code, key override, and any paired Bluetooth or keycard — before closing the door. Some Unican locks run a brief firmware handshake after power is restored, and the lock will not accept all inputs until that sequence completes.

Low battery warning immediately after fitting a new cell

Some Unican 502238 units display a low battery indicator even after a fresh battery is installed. This usually means the battery voltage is slightly below the lock's detection threshold — either from a battery that has been sitting in storage too long, or from a cell that was stored in a hot environment and self-discharged. Check the battery compartment contacts for corrosion from the old cell, which can introduce resistance and cause a false low-voltage reading. Use a fresh cell with a resting voltage confirmed at or above 9V before fitting.

Lock not responding after battery swap

If the Unican lock shows no response after a new battery is installed — no keypad lights, no motor movement, no beep — the lock's control board may not have completed its power-on reset. Remove the battery, wait 30 seconds to allow any residual charge in the board's capacitors to drain, then reinsert the battery firmly. Verify the battery is seated with correct polarity; reversed installation on these locks causes no response with no visible error. If polarity is correct and the lock still does not respond, check that the battery contacts in the compartment are making clean, firm contact with the cell terminals.