Devices, systems, and techniques for identifying a dendrite material within a battery. The method comprising receiving, by a battery management system, an output from sensing circuitry within the battery indicative of a first voltage level, detecting, by the battery management system, a change from the first voltage level to a second voltage level that is indicative of an internal short within a sensing sheet, determining by the battery management system, a resistance and a two-dimensional position of the internal short within the sensing sheet, and identifying, by the battery management system, a dendrite material based on the resistance of the internal short.