Co‐Crosslinked Water‐Soluble Biopolymers as a Binder for High‐Voltage LiNi0.5Mn1.5O4|Graphite Lithium‐Ion Full Cells. Issue 10 (14th April 2020) - Kuenzel, Matthias
Abstract: The use of water‐soluble, abundant biopolymers as binders for lithium‐ion positive electrodes is explored because it represents a great step forward towards environmentally benign battery processing. However, to date, most studies that employ, for instance, carboxymethyl cellulose (CMC) as a binder have focused on rather low electrode areal loadings with limited relevance for industrial needs. This study concerns the use of natural guar gum (GG) as a binding agent for cobalt‐free, high‐voltage LiNi0.5 Mn1.5 O4 (LNMO), which realizes electrodes with substantially increased areal loadings, low binder content, and greatly enhanced cycling stability. Co‐crosslinking GG through citric acid with CMC allows for an enhanced rate capability and essentially maintains the beneficial impact of using GG as a binder rather than CMC only. Lithium‐ion full cells based on water‐processed LNMO and graphite electrodes provide a remarkably high cycling stability with 80 % capacity retention after 1000 cycles at 1 C. Abstract : Great gum : The use of crosslinked guar gum as a binder for high‐voltage LiNi0.5 Mn1.5 O4 allows increased mass loadings, decreased binder contents, and enhanced cycling stability with a capacity retention of 80 % after 1000 cycles in LiNi0.5 Mn1.5 O4 |graphite full cells. Co‐crosslinking with carboxymethyl cellulose further improves the rate capability to render the aqueous electrode preparation a viable option for commercial applications.