The CSC Model 4400 Isothermal Microcalorimeter (IMC) has been used extensively for battery studies. Microcalorimetry offers the advantage of detecting all reactions taking place within the battery even parasitic reactions which limit shelf-life. The comparison of the heat produced by a complete battery versus the heat produced by partial cells or batteries fabricated without one or more components (e.g. cathode, anode, electrolyte, separator, etc.), can serve to identify the origin of non-current-producing reactions.