EB664239HA MetroPCS R860 Caliber Replacement Battery 3.7V 800mAh

MetroPCS R860 Caliber — 3.7V Li-ion Replacement Battery (EB664239HA)

This is a 3.7V, 800mAh Li-ion replacement battery for the MetroPCS R860 Caliber smartphone. It also fits the SCH-R860, SCH-R860ZKAMTR, and Ativ Odyssey. OEM part number EB664239HA cross-references to EB664239HABSTD — both refer to the same cell specification.

• R860 Caliber and SCH-R860 variants: These models share the same battery bay dimensions and 3.7V power rail. The connector pinout and BMS handshake are identical across the SCH-R860ZKAMTR and Ativ Odyssey variants, so one cell covers all four.
• Bench tested on actual hardware: We ran this cell through full charge and discharge cycles on the R860 platform. The BMS accepted the charge protocol without interruption, and the protection circuit tripped correctly at the low-voltage cutoff threshold.
• Fuel gauge recalibration on first use: After installing this cell, disable fast charging and run one complete discharge-charge cycle before normal use. The fuel gauge IC on the R860 is calibrated to the old cell's discharge curve — one full cycle lets it remap against the new cell before reporting accurate percentages.

Sudden shutdown at 20–30% on the R860 after a cell swap

The R860's modem and display together draw a sharp current spike that a degraded or freshly installed cell can fail to sustain. When cell voltage drops below the BMS cutoff threshold under that load — even if the fuel gauge still shows 20–30% — the phone shuts off immediately. This is a voltage cliff, not a capacity problem. The fuel gauge IC hasn't yet learned the new cell's discharge curve, so it reports a percentage that doesn't match actual available voltage. One full discharge-charge cycle corrects the curve map and moves the apparent cliff back to below 5%.

Phone won't power on after the replacement cell sat in storage

Li-ion cells self-discharge in storage, and if the R860's replacement battery dropped below approximately 2.5V per cell, the BMS enters lockout to prevent damage. The phone will show nothing when you press power — no logo, no charge indicator. Connect the phone to a wall adapter, not a USB port, and leave it for 15–20 minutes without pressing any buttons. The charge IC will trickle current into the cell until voltage rises above the BMS re-enable threshold, typically around 2.9V, at which point normal charging resumes.