Samsung SGH-J200 Replacement Battery AB533640BE 3.7V 800mAh

Samsung SGH-J200 — 3.7V Li-ion Replacement Battery (AB533640BE)

This is a 3.7V, 800mAh Li-ion cell rated at 2.96Wh, built to the AB533640BE specification. It fits the Samsung SGH-J200, a compact candybar-style mobile phone from the mid-2000s. Install it when the original cell no longer holds enough charge to get through a full day of use.

• SGH-J200 fit: The J200 uses a slim, low-capacity single-cell pack at 3.7V nominal. The AB533640BE form factor matches the contact placement and physical dimensions (43.72 × 35.49 × 4.94mm) exactly, so the battery seats and latches without modification.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on the J200 platform. The protection circuit handled end-of-charge cutoff cleanly at 4.2V and triggered undervoltage lockout before the cell dropped below safe floor voltage.
• Fuel gauge recalibration after installation: After fitting a new cell, run one complete discharge down to automatic shutoff, then charge uninterrupted to 100% before resuming normal use. The J200's fuel gauge IC was calibrated to the old cell's discharge curve — one full cycle resets its reference and stops the percentage counter from reading inaccurately.

Sudden shutdown at 20–30% on the SGH-J200 after a cell swap

The J200 shuts down abruptly in the 20–30% range when the fuel gauge IC's stored discharge curve no longer matches the new cell's actual voltage profile. The phone's software reads a safe percentage, but the real cell voltage drops sharply under the load of an incoming call or backlight burst. That voltage cliff triggers the protection circuit before the gauge catches up. One full discharge-to-shutoff and uninterrupted recharge corrects the IC's reference data and eliminates the false cutoff.

Phone warm near the battery compartment on the first few charges

A new Li-ion cell has higher internal impedance than a broken-in one, so the charge IC pushes slightly more voltage across that resistance during the constant-current phase — that converts to heat. On the J200 this is most noticeable in the first two or three cycles and fades as the cell's impedance settles. Keep the phone out of a case or pocket during those early charges so heat can dissipate from the plastic back cover. If warmth persists past the third full cycle, measure the battery contact voltage at full charge — it should read 4.15–4.20V.