Batteries　as　energy　storage　instruments　are　widely　used　in　electric　vehicles,　uninterrupted　power　supply　(UPS),　communications　and　random　fluctuations.　The　state　of　health　(SOH)　for　batteries　has　a　significant　impact　on　traffic　safety,　communication　reliability　and　energy　efficiency.　The　performance　of　batteries　is　affected　by　the　aging　of　batteries　with　the　increase　of　service　time.　Due　to　the　interaction　of　various　factors,　and　the　battery　is　a　highly　coupled,　complex　mechanism,　non-linear　parameter　change　system,　the　characterization　of　battery　aging　phenomenon　is　very　complex.　In　this　paper,　the　existing　SOH　estimation　methods　for　batteries　are　reviewed　and　classified　in　different　fields.　©　2019　IEEE.