Study on the stability of Li2MnSiO4 cathode material in different electrolyte systems for Li-ion batteries

Investigation on the Thermal Stability of Li2MnSiO4‐Based Cathodes for Li‐ion Batteries: Effect of Electrolyte and State of Charge

“…[41][42][43][44] Theh ydrolytic decomposition of LiBOB leads to products that are less toxic and corrosive than the HF produced from the decomposition of LiPF 6 .I n ap revious publication, we reported the impact of HF formation on Li 2 MnSiO 4 cathode materialu nder storage conditions,s howing that the pristine orthosilicate structure is highly susceptible to HF formed during LiPF 6 decomposition whereasi ti ss table from as tructural and morphological point of view in aL iBOB-based electrolyte. [32] In the study presentedh ere,t he thermal behavior of discharged Li 2 MnSiO 4 -based electrodes in LiPF 6 -based electrolytei s compared with the thermal behavior in aL iBOB-based electrolyte.I nb oth cases the electrodes were charged to 4.8 V and then discharged to 2V (SOC position3,s ee Figure 3). Thed ischarge cut-off was chosen to avoid film formation reactionsb etween LiBOB and carbon that occur at lower potentials.…”

“…[29][30][31] TheH Fp roduced is responsible for corrosion and degradation of active and inactive components of the cell, leading to an overall fadingo ft he battery performance.D ue to the strong affinityb etween fluorine and silicon atoms, HF rapidly reacts with Li 2 MSiO 4 ,r esultingi nd issolution of metal ions into the electrolyte. [32,33] Although these side reactions are mitigated in ac omposite electrode,i nw hich the contact area between the electrolyte and the active phase is reduced by the presence of other electrode components (e.g.,b inder, conductive agents), they can occur during both storage and cycling and reduce the electrochemical performanceo f Li 2 MnSiO 4 -based electrodes. [32] Moreover, an extended working potential range linked to high-energyc athodes such as Li 2 MnSiO 4 can result in as ignificant hazard increase for the cell.…”

“…[32,33] Although these side reactions are mitigated in ac omposite electrode,i nw hich the contact area between the electrolyte and the active phase is reduced by the presence of other electrode components (e.g.,b inder, conductive agents), they can occur during both storage and cycling and reduce the electrochemical performanceo f Li 2 MnSiO 4 -based electrodes. [32] Moreover, an extended working potential range linked to high-energyc athodes such as Li 2 MnSiO 4 can result in as ignificant hazard increase for the cell. Thel ithium phospho-olivine family represents ac lear example of this problem.…”

Insights into the Impact of Impurities and Non‐Stoichiometric Effects on the Electrochemical Performance of Li2MnSiO4

“…[3,4,[6][7][8] The high reactivity of the active material towards HF,w hich is produced from the decomposition of standard electrolyte systems, furtherc ontributes to the reductiono ft he electrochemical performance. [9] Few studies contradictt hese findings, and the synthesis procedures include, for example, the use of extremely high pressures or mesoporousc arbonsp repared by nanocasting. [10][11][12][13] Regardless of the synthesis route applied, acommon challenge of this material is to obtain ap ure phase.…”

Applications of Conventional Vibrational Spectroscopic Methods for Batteries Beyond Li‐Ion

“…Wohlfahrt‐Mehrens and co‐workers found that Li 2 MnSiO 4 cathode material forms HF in LiPF 6 ‐based electrolyte by ATR FTIR technology. However, Li 2 MnSiO 4 is stable in the lithium bis‐oxalatoborate electrolyte . Ozanam and co‐workers employed ATR FTIR mode (Figure b) to investigate the electrochemical processes of amorphous silicon film .…”