Franklin Wireless R526 Compatible Battery 3.7V 1450mAh

Franklin Wireless R526 / R536 Series — 3.7V Li-ion Replacement Battery (YSQ2010KB001861)

This 3.7V Li-ion battery at 1450mAh (5.37Wh) replaces the original pack in the Franklin Wireless R526, R526A, and R536 mobile hotspots. These are portable Wi-Fi devices that convert a cellular signal into a local wireless network. Swap in this battery when the original no longer holds charge or the device shuts down unexpectedly during a session.

• R526, R526A, and R536 compatibility: All three models share the same battery bay dimensions, connector pinout, and BMS communication protocol — the cellular modem and Wi-Fi radio draw from the same cell using identical voltage rails across the series.
• Bench tested on actual hardware: We ran this cell against the R526 BMS under simultaneous modem and Wi-Fi load. The BMS handshake completed without error, charge cycles registered correctly, and the protection circuit tripped at the expected low-voltage threshold.
• Ventilation during extended hotspot sessions: Keep the R526 on a hard, flat surface — not a bag or pocket. When connected devices are far from the hotspot, the cellular radio ramps to full output power. That heat builds directly against the battery. A clear surface lets the case vent it away.

Why the R526 drops all connected devices mid-session on a new battery

The R526 runs two high-draw systems simultaneously — the cellular modem and the Wi-Fi radio. At maximum connected devices, the combined current draw spikes sharply. If the cell's internal resistance is elevated — common in aged or counterfeit packs — voltage sags below the modem's operating floor for a fraction of a second. The BMS reads that as a fault and cuts output. A fresh cell with correct internal resistance holds voltage steady through those draw spikes and keeps the session alive.

R526 not powering on after sitting unused for several weeks

Li-ion cells self-discharge at roughly 2–3% per month at room temperature. If the R526 was stored with a low charge, the cell can drop below the BMS's minimum boot voltage — typically around 3.0V — and the device will not respond to the power button. Connect to a charger for at least 20–30 minutes before attempting to power on. If the OEM battery will not recover past 3.0V after that charge window, replacement is the next step.