Battery tester with high precision

摘要

The battery tester has a casing having an input device and two detecting wires, a microprocessor, a loading unit and a battery power status detector. The microprocessor builds a strategic decision process therein to determine a discharge time of a battery according to an output current, a preset load having 1/N CCA (Cold Cranking Amps) and a preset loading time inputted from the input device. Therefore, the battery tester can detect the health of batteries with different capacities and provides accurate detecting results.

主权项

1. A battery tester with high precision, comprising:
a casing having:
an input device serving to input a marked battery capacity (CCAB), a preset load (1/N CCAB) being 1/N of the marked battery capacity, and a preset loading time (TLOAD) of a battery, wherein N is a positive real number; andtwo detecting wires adapted to selectively connect to two electrodes of the battery; a microprocessor built in with a strategic decision process; a loading unit electronically connected to the microprocessor and connected to the detecting wires; a switch electronically connected between one of the detecting wires and the loading unit, and controlled by the microprocessor; and a battery power status detector electronically connected to the microprocessor to detect a initial voltage (VB) and an output current (IB) of the battery and reporting the initial voltage and the output current to the microprocessor; wherein the strategic decision process is performed by the microprocessor and has steps of: (a) obtaining the marked battery capacity, the preset load and the preset loading time from the input device and the initial voltage of the battery from the battery power status detector; (b) connecting the loading unit to the battery and then reading the output current of the battery from the battery power status detector; (c) calculating an equation of discharging time with the output current, the marked battery capacity, the preset load and the preset loading time to determine a discharge time of the battery, wherein the equation of discharging time isTD=CCAB×1NIB×TLOAD where TD represents the discharge time of the battery; CCAB represents the marked battery capacity of the battery; N represents the positive real number used to divide the marked battery capacity of the battery to obtain the preset load that is equal to 1/N of the marked battery capacity (CCAB); IB represents the output current of the battery and is equal to the initial voltage (VB) divided by a fixed resistance of the loading unit; and TLOAD represents the preset loading time applied by the loading unit; (d) executing a detecting process to obtain a detecting curve.