A method and apparatus for determining the state of charge of a battery include use of multiple battery tests to provide complementary insight into battery condition before, during, and after battery charging. Battery testing is performed using a light resistive load, a heavy resistive load, a conductance...http://www.google.de/patents/US6144185?utm_source=gb-gplus-sharePatent US6144185 - Method and apparatus for determining the condition of a battery through the use of multiple battery tests
