LAUSR

Recently, there is a growing interest in very small micro-batteries with footprint in the 1 mm range, in particular for medical applications. For such small batteries, only the volume and not the weight matters. Generally, the practical energy density of such small cells is much lower than that of the active materials and it decreases with decreasing battery size. State-of-the-art micro-batteries have their limits when it comes to micro–sizes; their fabrication and packaging is such that the inner contact surface, wall thickness and the safety distance between anode and cathode (separator membrane) outweigh the active volume and thus significantly reduces the achievable volumetric energy density. Fig. 1 shows some characteristics of today’s rechargeable lithium-based micro-batteries.