The lifetime of Li-ion Batteries (LIB) depends on the reversible amount of Li ions and electrons (= active Li), defining Li inventory and cell capacity. Active Li loss (ALL) occurs at the negative electrode (= anode) predominantly via electrolyte reduction and formation of the solid electrolyte interphase (SEI). Nevertheless, given interference of the cathode, anode R&D is challenging in a LIB full cell. Replacing a LIB cathode with Li metal is common in anode R&D, though applied test protocols do not represent the full cell situation, as (1) anodes get fully re-charged each cycle, i.e., not considering limited Li inventory and ALLs from previous cycles and (2) cycling with a fixed charge cut-off voltage (COV) can lead to huge capacity deviations during experiments as already marginal overvoltages can reach the COV notably earlier, thus resulting in notably lower charge capacities, in particular for plateau-like charge profiles like graphite. Here, an advanced charging protocol is provided, which adjusts the specific charge capacities of an individual cycles to previous cycle discharge capacities, thus considering ALLs, and allows anode R&D involving fast screening and simulation of numerous parameters by representing full cell conditions, e.g., mass loading, N/P ratio, state-of-charge and even prelithiation degree, as exemplarily shown for zero excess LMBs (= “anode-free”)- and graphite/silicon-based anodes.

Here in this paper we were able to use the advanced testing protocol to mimic and limit capacity to levels similar to typical positive electrodes with the same behavior as seen with Si-Gr || Li or oversized LFP electrodes hence showing similar behavior

The advanced testing protocol allows fast screening in anode R&D such as mass loading or state-of-charge (SOC) utilization. Also, the effect of cutoff voltages on the discharge potential is highlighted

The degree of prelithiation (DOPL) can also be screened quickly to find the optimal