Charger for a battery pack, charging system and method of charging

A charging system comprising:

• a battery pack comprising:
• a battery input line;
• one or more electrochemical cells electrically connected to the battery input line;
• at least one blocking device disposed in the battery input line and configured to allow a unidirectional flow of current from the battery input line to the one or more electrochemical cells;
• and
• a battery sense line electrically connected to the battery input line between the one or more electrochemical cells and the at least one blocking device, such that the battery sense line is configured to detect a voltage drop across the at least one blocking device;
• and
• a charger configured to be selectively coupled to the battery pack, the charger comprising:
• a charger integrated circuit (IC) comprising an input pin, an output pin, and a sense pin, wherein the input pin is configured to be electrically connected to a power source, and wherein the charger IC is configured to provide an output voltage at the output pin;
• a charger output line electrically connected to the output pin of the charger IC, the charger output line configured to be electrically connected to the battery input line upon coupling of the battery pack to the charger;
• a charger sense line configured to be electrically connected to the battery sense line upon coupling of the battery pack to the charger;
• and
• an analog switch electrically disposed between the charger sense line and the battery sense line, such that:
• the analog switch is configured to electrically disconnect the sense pin from the charger sense line when the battery pack is disconnected from the charger;
• the analog switch is configured to electrically connect the sense pin of the charger IC to the battery sense line of the battery pack upon sensing of the battery pack by the charger;
• and
• the charger IC is configured to control the output voltage based on a voltage detected at the sense pin of the charger IC, wherein the voltage detected at the sense pin of the charger IC is based on the voltage drop across the at least one blocking device.

A method of charging a battery pack using a charger having a charger integrated circuit (IC), the method comprising:

• electrically disconnecting, by an analog switch, a sense pin of the charger IC from a charger sense line of the charger when the battery pack is disconnected from the charger;
• electrically connecting, by the analog switch, the sense pin of the charger IC to the charger sense line upon sensing the battery pack;
• and
• providing, by the charger IC, an output voltage at a charger output line based on a voltage detected at the sense pin of the charger, wherein the charger output line is electrically connected to one or more electrochemical cells of the battery pack upon coupling of the battery pack to the charger.