[Scalable Capacity Expansion] - 5120Wh per pack with 4,000+ cycles to 80% capacity. Expand up to 6 B500K per Apex 300. 3 Apex 300 with 18 B500Ks achieve an incredible 100kWh capacity.[Widely Compatible] - B500K works with past and future BLUETTI portable power stations including AC200L AC200MAX AC300 AC500 and Apex 300. This listing includes a P090A cable compatible with most power stations. AC500 requires a separate P150D cable.[Next-Gen Design Architecture 2.0] - The B500K expansion battery bulit with a cable-free internal layout, wireless internal structure lowers failure risks and saves space, resulting in a more compact, easy-to-move product.[Usage Ecosystem] - Beyond capacity expansion, the B500K works with BLUETTI accessories for versatile charging and discharging: SolarX 4K (4000W), Alternator Charger (560-1000W), Hub D1 (700W DC), and future accessories.[What You Get] - BLUETTI B500K expansion battery, P090A-P090A battery connection cable, and user manual.