Barnes & Noble GlowLight Plus 7.8 Replacement Battery PR-285084 3.7V

Barnes & Noble GlowLight Plus 7.8 / BNRV700 — 3.7V Li-Polymer Replacement Battery (PR-285084)

This 3.7V, 1500mAh lithium-polymer battery replaces the OEM cell in the Barnes & Noble GlowLight Plus 7.8 (model BNRV700) e-reader. It fits the PR-285084 slot directly and restores power to the e-ink display, processor, and front-lighting system. Use the capacity figure from the product data — 1500mAh / 5.55Wh — as the reference spec.

• GlowLight Plus 7.8 and BNRV700 fit: Both model designations refer to the same hardware generation. They share the same battery bay dimensions (84.15 × 49.50 × 2.70mm), the same flex connector, and the same charge IC handshake — one cell covers both.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a BNRV700 unit. The BMS accepted the new cell without fault flags, the charge IC reached termination cleanly, and voltage under e-ink refresh load held within spec.
• Post-swap fuel gauge reset: After installing this battery, run the device down to automatic shutoff, then charge uninterrupted to 100%. The GlowLight's fuel gauge IC is calibrated against the old cell — skipping this cycle causes the percentage meter to read inaccurately from the first hour of use.

GlowLight Plus 7.8 shutting down at 15–25% remaining

The e-ink display refresh and front-lighting system draw current simultaneously when page turns happen. On a new cell the fuel gauge IC hasn't mapped the voltage curve yet, so it misreads a brief voltage dip under that combined load as a critically low state. The device triggers a protective shutdown before the cell is actually empty. One full discharge-to-shutoff and uninterrupted recharge cycle gives the fuel gauge enough data to map the real curve and stops the early cutoff.

Battery percentage jumping or dropping faster than expected from 100%

This is fuel gauge drift — the IC on the GlowLight uses coulomb counting referenced to the old cell's internal resistance profile. A new cell has lower internal resistance, so the same current draw reads as a larger state-of-charge drop than it actually is. The fix is a single calibration cycle: discharge fully until the device shuts itself off, then charge to 100% without interruption. After that cycle, percentage readings stabilise at real values.