Lithium-ion battery software safety protection

Production Li-ion batteries include hardware and software safety protection. The hardware protection includes PTC (positive temperature coefficient) thermistor switch, electrical circuit disconnect and rupture vent. The software protection involves a charging algorithm (charging to ultimate voltage), which is used with internal electrical circuitry (cell voltage control and equalization circuit). This paper discusses a specific charging algorithm and additional software protection features associated with hard, soft and chemical shunt recognition.