Patent attributes
A secondary battery for cycling between a charged and a discharged state, wherein a 2D map of the median vertical position of the first opposing vertical end surface of the electrode active material in the X-Z plane, along the length LE of the electrode active material layer, traces a first vertical end surface plot, EVP1, a 2D map of the median vertical position of the first opposing vertical end surface of the counter-electrode active material layer in the X-Z plane, along the length LC of the counter-electrode active material layer, traces a first vertical end surface plot, CEVP1, wherein for at least 60% of the length LC of the first counter-electrode active material layer (i) the absolute value of a separation distance, SZ1, between the plots EVP1 and CEVP1 measured in the vertical direction is 1000 μm≥|SZ1|≥5 μm.