Field trials on DC-power-supply system equipped with 80-ah stationary lithium-ion secondary batteries

A DC-power-supply system with a maximum output current of 30 A was developed using stationary 80-Ah lithium-ion batteries and performance tests were carried out in laboratories and a base transceiver station offering actual services. The system was designed for an outdoor setting. The lithium-ion batteries had recharge characteristics evaluated by a method of constant-current and constant-voltage charge and delivered almost equal discharge at current rates that ranged between and 1-10 hr. Their cell voltage was over 3.6 V per cell during discharge at the same current rates. The weight of the batteries was reduced to about a quarter and the volume of the system was reduced to about a third by applying the lithium-ion batteries, compared to a conventional system with VRLA batteries. The composition, fundamental characteristics, and field-test results for the DC-power-supply system are also described.