Abstract: An electronic battery tester for testing a storage battery determines a condition of the battery. The condition is a relative condition and is a function of a dynamic parameter of the battery and an empirical input variable.

Abstract: An apparatus and method for supplying energy to a vehicle battery is provided. The apparatus includes a positive connector that couples to a positive terminal of the vehicle battery and a negative connector that couples to a negative terminal of the vehicle battery. A battery charger applies a charge signal to the vehicle battery through the positive and negative connectors to thereby charge the vehicle battery. A jump-start booster pack, coupled to the battery charger, can optionally provide starting energy to the vehicle battery through the positive and negative connectors. The booster pack can be charged by the charge signal.

Abstract: An apparatus configured to couple to a battery contact is provided. The apparatus includes an electrical connector for connection to a battery contact and an environment sensor integrated with the electrical connector, the environment sensor senses changes in a battery environment during battery charging or testing. In addition, a method of coupling an electrical circuit to a battery contact is provided.