Given　that　battery-powered　electric　vehicles　and　other　power　equipment　put　forward　higher　requirements　for　long　recharge　mileage,　the　development　of　high-performance　lithium　batteries　(LBs)　has　become　necessary.　Accordingly,　one　of　the　effective　ways　to　achieve　this　is　to　increase　the　cell　voltage　and　energy　density　of　LBs.　However,　these　high-cell-voltage　and　high-energy-density　LBs　face　the　challenges　of　severe　electrolyte　decomposition　and　electrode　corrosion　in　a　high-voltage　environment.　In　this　review,　the　issues　associated　with　the　electrolyte　for　high-cell-voltage　and　high-energy-density　LBs　are　comprehensively　reviewed　in　terms　of　the　types　of　electrolytes　and　electrolyte　additives,　their　functional　mechanisms　and　their　performance　validation.　Also,　we　focus　on　electrolyte　ion　solvation　and　the　internal　solvent　structure　based　on　both　solution　chemistry　and　solvation　theory.　Both　the　high　concentration　strategy　and　solvent　modification　are　identified　to　be　effective　in　improving　the　performance　of　high-cell-voltage　and　high-energy-density　LBs.　In　addition,　the　selection　of　new　organic　lithium　salts　instead　of　traditional　lithium　salts　and　electrolyte　additive　design　have　also　been　identified　to　be　important　ways.　To　facilitate　further　research　and　development,　herein,　some　technical　challenges　are　analyzed　and　the　future　research　directions　for　overcoming　the　discussed　challenges　are　also　proposed.　This　review　may　provide　theoretical　support　for　electrolyte　design　and　additive　selection　for　high-cell-voltage　and　high-energy-density　LBs　in　future.　©　2022　The　Royal　Society　of　Chemistry.