The ML-DYS21 Replacement Battery by Mighty Max is Designed for for Dyson Vacuum, Its an Li-ion Rechargeable battery that keeps Dyson running at peak performance.  ML-DYS21 can be charged or discharged as needed without loss of capacity.
The ML-DYS21 battery is fully compatible with: 12097, 912433-01, 912433-03, 912433-04, BP-01 
Fit Models: Dyson DC16 Dyson DC16 Animal, Dyson DC16 Pink, Dyson DC16 Root 6, Dyson DC16 Car and Boat, Dyson DC16 ISSEY MIYAKE exclusive, Dyson DC16 Motorhead
Battery Specifications:
Voltage: 21.6V
Amperage: 1500mAh
Chemistry: Li-ion
Warranty: 1 Year
Genuine Mighty Max battery Product

• 21.6 Volt 1500mAh Li-Ion Battery - 2 Pack
• Mighty Max batteries are made with the highest quality Li-ion material
• No memory effect which can be charged or discharged without loss of capacity
• Fully Compatible with Dyson DC16 Vacuum
• 1 Year Warranty

21.6 Volt 1500mAh Li-Ion Battery - 2 PackMighty Max Battery