Lithium-ion Battery for B1 500 AirTTL from Profoto will give you up to 220 full power flashes (325 flashes with new Profot B1x model) and thousands of minimum power flashes on a 2 hour charge from the 2.8A multi-voltage charger. The 4.5A quick charger shortens that time to 1 hour. Fuel gauge-type LEDs on the battery and both the optional chargers allow you to monitor charge progress. 220 full Power Flashes …