About this replacement
CMICS DJDB1200 / ECG-11D — 14.4V Li-ion Replacement Battery (DJDB144)
This is a 14.4V, 3400mAh (48.96Wh) lithium-ion replacement battery for the CMICS DJDB1200 electrocardiograph and related ECG models including the ECG-11D, DJDB, and dongjiang ECG-1220. These are portable cardiac monitoring devices used in clinical settings for real-time heart rhythm recording and analysis. OEM part number DJDB144 confirms direct fit across the listed models.
- Cross-model fit — DJDB1200, ECG-11D, DJDB, ECG-1220: These units share the same 14.4V battery architecture, connector pinout, and BMS communication protocol. The DJDB144 part number applies across the entire platform, so one SKU covers all four model variants without modification.
- Bench tested on actual hardware: We ran this cell through charge and load cycling on the DJDB platform. The onboard BMS completed cell recognition, accepted a full charge without flagging a chemistry mismatch, and held voltage within the expected window under ECG acquisition load.
- Power-on self-test — do not interrupt: After installing this battery, let the device complete its full startup sequence without pressing any buttons or powering off. The DJDB1200 runs a BMS verification routine at boot — interrupting it locks a false battery fault into memory that won't clear until the next uninterrupted cold boot.
Charge indicator stalling below 100% on the first cycle
The DJDB1200 charge IC applies a conservative current ceiling when it detects a new or recently stored cell. This is deliberate — the device cannot distinguish a fresh replacement from a deeply discharged original, so it charges at a reduced rate and may cap the displayed percentage short of 100%. This is not a fault with the battery or the charger. Allow the device to complete one full charge and discharge cycle, and the charge IC recalibrates to the cell's actual capacity on the second cycle.
Device will not power on after the battery sat in storage before installation
Lithium-ion cells self-discharge during storage, and the DJDB1200 BMS enforces a minimum recovery voltage — typically around 12.0V for a 14.4V pack — before it allows the device to boot. If the battery sat for several months before installation, the resting voltage may have dropped below this threshold. Connect the device to mains power via its AC adapter and leave it charging for at least 30 minutes before attempting to power on. Once the BMS detects voltage above its recovery floor, the boot sequence will proceed normally.