A stretchable alkaline battery based on a embedded stretchable silver fabric is fabricated with an open circuit potential (OCV) of 1.5 V and capacity of 3.775 mAh/cm2. No drop in discharge capacity is observed with strain up to 100%. Two batteries connected in series continued to power a red LED even when stretched to 150% and twisted by 90 degrees.

A model is proposed and used to parameterize the surface-temperature distribution and electrical response for A123 20 Ah LiFePO4 prismatic cells. The cell interior is described by a porous-electrode charge-transport model based on Newman-Tobias theory, which is coupled to a local heat balance. Simulation output depends on only a few observable dimensionless quantities, allowing parameter estimation via iterative optimization schemes that directly compare computed results with experimental voltage and surface-temperature measurements.Despite the neglect of mass-transport limitations within Newman-Tobias theory, the model accurately predicts the dynamic terminal voltage, as well as the minimum, maximum, and surface-averaged temperature on the cell exterior. The electrochemical and thermal properties extracted from square-wave cycling data with various excitation amplitudes (2 C and 4 C) and short charge/discharge periods (50 s and 100 s) compare well with literature values, showing that it is possible to infer internal material properties by fitting external measurements. The temperature dependence of parameters has clear signatures in the observed voltage.

Compliant energy storage has not kept pace with flexible electronics. Herein we demonstrate a technique to reinforce arbitrary battery electrodes by supporting them with mechanically tough, low‐cost fibrous membranes, which also serve as the separator. The membranes were laminated to form a full cell, and this stacked membrane reinforcement bears the loads during flexing. This technique was used to make a high energy density, nontoxic Zn–MnO2 battery with printed current collectors. The Zn and MnO2 electrodes were prepared by using a solution‐based embedding process. The cell had a nominal potential of 1.5 V and an effective capacity of approximately 3 mA h cm−2. We investigated the effect of bending and fatigue on the electrochemical performance and mechanical integrity of the battery. The battery was able to maintain its capacity even after 1000 flex cycles to a bend radius of 2.54 cm. The battery showed an improvement in discharge capacity (ca. 10 %) if the MnO2 electrode was flexed to tension as a result of the improvement of particle‐to‐particle contact. In a demonstration, the flexible battery was used to power a light‐emitting diode display integrated with a strain sensor and microcontroller.

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