About this replacement
Asus ROG Chakram — 3.7V Li-Polymer Replacement Battery (FT802540P)
This is a 3.7V 800mAh Li-Polymer replacement battery for the Asus ROG Chakram wireless gaming mouse. It uses OEM part number FT802540P and fits directly into the Chakram's internal battery bay. Swap it in when the original cell no longer holds charge or the mouse shuts off mid-session.
- ROG Chakram compatibility: The Chakram uses a compact Li-Polymer cell on a 3.7V rail with a built-in BMS that monitors cell voltage and cuts power at the low-voltage threshold. This replacement matches that voltage, the physical 41.00 × 24.60 × 8.00mm footprint, and the connector orientation the mouse expects.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the Chakram platform and confirmed the BMS handshake completes correctly — the mouse charges via USB-C without throwing a fault, and the battery indicator reports state of charge accurately in Armory Crate.
- Post-swap RGB draw awareness: The Chakram's RGB lighting and high-polling wireless stack draw significantly more current than a standard office mouse. If you run full RGB at 1000Hz polling, the BMS will see higher continuous drain — reduce RGB brightness in Armory Crate to extend cycle count on this cell.
Why the ROG Chakram drops offline after a battery swap
When the Chakram loses power completely during a battery replacement, the wireless receiver can lose its active pairing session. The mouse stores connection state in volatile memory, so a full power loss can clear it. If the mouse doesn't reconnect automatically after installing the new battery, unplug the USB receiver, wait 10 seconds, and replug it. If that fails, hold the pairing button on the underside of the mouse until the LED flashes, then let the receiver re-establish the link.
Pointer stuttering and tracking lag on a charged Chakram
Stuttering on a battery that reads as charged usually means cell voltage is sagging under load rather than sitting at true resting voltage. The Chakram's wireless polling at 1000Hz combined with active RGB creates brief current spikes that drag a degraded cell below the stable operating threshold. The BMS doesn't shut the mouse off — it throttles transmission rate instead, which shows up as lag or dropped tracking points. If a new battery doesn't resolve this after a full charge cycle, check that the USB receiver is plugged directly into a powered USB port, not a hub.