초록 ▼

The invention relates to apparatus for determining the state of charge of electric storage batteries. The apparatus makes use of known quiescent battery (16) terminal voltage recovery characteristics after a prior energy transfer to predict the ultimate steady state terminal voltage as a measure of

The invention relates to apparatus for determining the state of charge of electric storage batteries. The apparatus makes use of known quiescent battery (16) terminal voltage recovery characteristics after a prior energy transfer to predict the ultimate steady state terminal voltage as a measure of state of charge. In one embodiment, this is accomplished by using a voltage-controlled oscillator (18) and a reversible counter (20) to measure a first battery (16) terminal voltage over a fixed time interval, storing that measurement in a register (24), measuring a second terminal voltage by reversing the counter (24) and counting the counter down for an identical fixed interval of time, and then determining the slope of the voltage recovery (at) (26) (30) based upon the difference between the two voltage measurements as evidenced by the count remaining in the counter (20) and adding a factor (at) (74) to the first voltage measurement based upon the voltage difference measurement to determine a predicted steady state voltage as an indication (28) of the charge on the battery.

대표청구항 ▼

Apparatus for testing a quiescent battery for determining the state of charge of that battery comprising means for taking battery terminal voltage measurements, means for storing a first battery terminal voltage measurement, means for comparing a second battery terminal voltage measurement taken at

Apparatus for testing a quiescent battery for determining the state of charge of that battery comprising means for taking battery terminal voltage measurements, means for storing a first battery terminal voltage measurement, means for comparing a second battery terminal voltage measurement taken at a subsequent time with said first battery terminal voltage measurement and operable to determine the direction of voltage change of said second voltage measurement from said stored first voltage measurement and to generate at least one signal indicating the direction of voltage change, and visual indicating means connected to said comparison means to receive said direction of voltage change signal for providing a visual indication of the direction of voltage change as an indication as to whether the battery was last subjected to charge or discharge.