Makita BL1840B 18V LXT Lithium-Ion 4.0Ah Battery, Black - Amazon.com
How to disassemble recent Makita battery packs to salvage cells - YouTube
Makita 18V LXT Lithium-Ion High Capacity Battery Pack 4.0Ah with Fuel Gauge and Charger Starter Kit BL1840BDC1 - The Home Depot
18v 3ah 4ah 5ah 6ah Li-ion Battery Rechargable Battery For Makita 18v Battery Bl1840 Bl1850 Power Tool With Led Indicator - Voltage Regulators/stabilizers - AliExpress