Patent ID: 8685255

Claim:
A method for efficiently softening water in a cell comprising a water inlet, a water outlet, a cathode current collector and an anode current collector, the method comprising: during a charge cycle, creating a stream of clean water in a direction from the inlet to the outlet at a flow rate F1, while applying a charge voltage of between about 0.5V and about 1.3V between the cathode current collector and the anode current collector of a cell for a period of time T1; during a discharge cycle, creating a stream of waste water in the direction from the inlet to the outlet at a flow rate F2, while applying a discharge voltage between about âˆ’1.3V and about âˆ’0.5 V between the cathode current collector and the anode current collector for a period of time T2; repeating the charge and discharge cycles C times, wherein C>1; and applying a regeneration voltage between 0.0 V and âˆ’1.3 V between the cathode current collector and the anode current collector to a stream of water in the direction from the inlet to the outlet at a flow rate F3, for a period of time T3 such that F1*T1*C/[F1*T1*C+F2*T2*C+F3*T3] is greater than or about equal to 0.7, wherein T3 is greater than T2.