Sokkia SDR8100 Replacement Battery 3.7V 3600mAh 20-36098-01

Sokkia SDR8100 — 3.7V Li-ion Replacement Battery (20-36098-01)

This 3.7V 3600mAh Li-ion battery replaces the OEM pack in the Sokkia SDR8100 data collector. The SDR8100 is a handheld field instrument used in land surveying and construction positioning. Capacity is 3600mAh — drawn from the product specification, not estimated.

• SDR8100 platform fit: The SDR8100 uses a single-cell Li-ion configuration at 3.7V nominal. This replacement matches the OEM voltage rail and physical form factor so the BMS handshake initialises correctly on first boot without any manual reset step.
• Bench tested on actual hardware: We cycled this pack under a combined scan-trigger and wireless-polling load profile. The BMS held the low-voltage cutoff threshold and did not trip spuriously during burst-draw events across the test sequence.
• First-shift preparation for SDR8100: Place the unit in its charging dock immediately after installing this pack and let it complete a full charge cycle before heading into the field. The scan-trigger inrush current is highest when cell voltage is near minimum, and a cell at full charge prevents false BMS cutoffs during the first data-collection session.

Why the SDR8100 drops its wireless link during rapid data capture bursts

The SDR8100 pulls simultaneously from two high-demand sources during active field work: the scan trigger circuit and the wireless radio polling the network. When cell voltage sags under that combined inrush, the BMS can momentarily throttle output to protect the cell, which the radio firmware reads as a link drop rather than a power event. A cell at partial state of charge has higher internal resistance and sags further under the same load. Keeping the pack above 3.5V under load — check with the SDR8100's internal battery status screen — eliminates most link-drop events caused by voltage sag.

SDR8100 charging dock shows an error light on a new pack

A new Li-ion pack shipped in storage mode can present at or below the dock's minimum charge-acceptance threshold, causing the cradle to flag an error rather than begin charging. The dock contacts on both the unit and the cradle also accumulate oxidation in field environments, raising contact resistance enough to trigger the same fault. Wipe the gold contacts on the battery pack and the dock rails with a dry cloth, reseat the unit firmly, and watch for the charge indicator to switch from error to active within 30 seconds. If it does not, connect via the USB charging port directly on the SDR8100 to bring the cell above 3.0V first, then return it to the dock.