Abstract: A signal, in the form of high power, low energy pulses that are generated on cables that are connected directly to the terminals of a low impedance battery, are transmitted between a memory device located on the battery and a data recorder located at the charger end of the battery charging cables. Information transfer between the battery memory device and a charger is done through the battery cables, eliminating the need for special connections. The high power, low energy pulses imposed on the battery cables may be detected at each end of the cables, in spite of the low impedance nature of large lead acid batteries. Pulses are created across the terminals of the battery using a fast acting switch (preferably a FET), a capacitor, and a current limiting resistor connected in series across the cables. When the switch is closed in response to an external command, high power, low energy pulses imposed at one end of the cables are detected at the other end of the cables.

Abstract: A memory device connected to a storage battery stores a battery identification code and other data such as present and maximum temperature and voltage, and information concerning the vehicle on which the battery is used. Information transfer between the battery memory device and a charger is done through the battery cables, eliminating the need for special connections. A high power, low energy pulse imposed on the battery leads may be detected at each end of the cables, in spite of the low impedance nature of large lead acid batteries. A method and apparatus for transmitting data on a pair of battery cables includes transmitting each data pulse as a plurality of short duration pulses whereby each short duration pulse is created by momentarily imposing a high power, low energy pulse at one end of the cables. These pulses are detected at the other end of the cables and are applied to a resettable multivibrator having a output pulse width slightly greater than the interval between said short duration pulses.