Huawei E5573 Replacement Battery HB434666RAW 3.7V 1150mAh

Huawei E5573 Series — 3.7V Li-ion Replacement Battery (HB434666RAW)

This is a 3.7V, 1150mAh Li-ion battery for the Huawei E5573 portable WiFi hotspot range. It fits the E5573, E5573S, E5573s-856, E5573s-852, and over a dozen additional E5573 variants. Swap it when your original cell no longer holds enough charge to get through a working session.

• E5573 series compatibility: All E5573 variants share the same 3.7V battery bay, connector pinout, and BMS handshake protocol. The HB434666RAW and HB434666RBC are interchangeable across the range — same physical dimensions (65.50 × 46.00 × 4.30mm), same communication lines.
• Bench tested on actual hardware: We ran this cell under combined WiFi broadcast and live LTE modem load. The BMS held voltage above the 3.2V cutoff through sustained multi-device draw and recovered cleanly after discharge cycles without triggering a protection latch.
• Ventilation during extended hotspot sessions: When connected devices are far from the hotspot, the cellular radio pushes to maximum transmit power. That heat sits directly against the battery. Keep the unit on an open surface — not in a bag or enclosed pocket — during long sessions to avoid sustained thermal stress on the cell.

Voltage sag under combined modem and WiFi load at maximum connections

The E5573 drives two power-hungry subsystems simultaneously — the LTE modem and the WiFi radio. At maximum connected clients, total draw can spike enough to pull cell voltage below the BMS cutoff threshold, causing an abrupt shutdown. A degraded original battery hits that threshold much earlier in the discharge curve than a fresh cell. Replacing the battery restores the full headroom between resting voltage and the BMS trip point, so the device can sustain peak load without cutting out.

Hotspot shows battery present but won't power on after sitting unused

Li-ion cells left uncharged for weeks self-discharge. If the cell drops below approximately 2.5V, the BMS enters deep-discharge lockout and the device will not boot — even when plugged into a charger, the unit may show no response. To recover, leave the hotspot connected to the OEM charger for 20–30 minutes without attempting to power it on; the charger trickle-charges the cell back above the BMS re-enable threshold. If the LED never responds after that window, the original cell has reached end of life and needs replacement.