Sato TH2 WMB405970 Replacement Battery 14.8V 1600mAh

Sato TH2 / MB400i Series — 14.8V Li-ion Replacement Battery (WMB405970)

This 14.8V 1600mAh Li-ion battery replaces the OEM pack in the Sato TH2, TH208, MB400i, and MB410i portable thermal printers. These are mobile label and receipt printers used in retail, logistics, and field operations. It matches the original voltage rail and connector spec for direct installation.

• TH2, TH208, MB400i, MB410i compatibility: All four models run the same 14.8V four-cell Li-ion pack with a shared BMS handshake protocol and identical physical connector. One battery fits the full series without modification.
• Bench tested on actual hardware: We ran this battery through charge and discharge cycles on the MB400i. The BMS responded correctly to the printer's motor-start current draw and held the voltage rail steady through paper feed and print head activation sequences.
• First-print calibration after install: After installing and fully charging, run five test prints before deploying the unit. The paper feed motor draws a higher current burst on a fresh cell, and printing a short calibration sequence confirms the BMS current profile is properly matched to the thermal head load.

Why the TH2 won't print after sitting unused for several weeks

Lithium-ion cells self-discharge during storage. If the TH2 sits unused long enough, the pack voltage can drop below the BMS minimum threshold — typically around 12V on a 14.8V four-cell pack. When that happens, the printer powers on but refuses to drive the thermal head or paper feed motor, because the BMS blocks load current to protect the cells. Recharging from this state takes longer than a normal cycle. If the charger doesn't trigger, connect the printer to a known-good USB power source briefly before placing it on the dock — this can wake the BMS enough to accept a full charge.

Faded or uneven print output when the battery is partially charged

The thermal print head in the TH2 is temperature-controlled by a voltage-regulated heating element. When battery voltage sags — typically below 13.5V under load — the element doesn't reach full operating temperature consistently. The result is faded characters or uneven density across a label. This isn't a head fault or a media problem. Charge the battery to full and test again. If print quality remains inconsistent at full charge, the original cell capacity has degraded and the pack needs replacement.