Patent ID: 7218118

Claim:
A method for monitoring a condition of a battery which is connectable to an electrical load, comprising the steps of: measuring a voltage characteristic of said battery during a measuring event subsequent to a connection event when a connection relationship between said battery and said electrical load is changed; storing a plurality of said measured voltage characteristics for a plurality of subsequent magnitudes of said measured voltage characteristics obtained during subsequent measuring events; providing a table of a plurality of pre-selected voltage values, including a threshold acceptability voltage value and a plurality of gradation voltage values; comparing said measured voltage characteristic to all three of the following: a) said pre-selected threshold acceptability voltage value; b) said pre-selected plurality of gradation voltage values; c) said stored plurality of measured voltage characteristics of said subsequent magnitudes; providing all three of the following in combination: 1) an indication of whether the condition of the battery is acceptable, according to said pre-selected threshold acceptability voltage value; 2) an indication of the grade of battery condition, according to said pre-selected plurality of gradation voltage values; 3) an indication of the trend of battery condition grade, according to said plurality of measured voltage characteristics.