About the BTI Battery
BTI L20M3P71-BTI 3-CELL 11.58V LI-ION BATTERY COMPATIBLE WITH 5B11A13107, L20L3P71, SB11A14634, 5B11A13108, L20M3P71, 5B11A14635, THINKPAD P16 GEN 1, X13 YOGA GEN 2 20W9, P16 GEN 1 21D7, X13 YOGA GEN 3, X13 YOGA GEN 2, X13 YOGA GEN 3 21AW, X13 YOGA GEN 2 20W8, X13 YOGA GEN 3 21AX