you can find all these elements in the SimPowerSystems library of Simulink, from version R2013 on. They are certainly good, easy to use and match adequately the behaviour of real devices.
If you have the simscape toolbox, using this http://www.mathworks.com/matlabcentral/fileexchange/36019-lithium-battery-model--simscape-language-and-simulink-design-optimization
you have a very good model of lithium battery model.
Then you can conveniently add your model to mechanics using simscape for devices like hybrid motor engine or hydraulic systems.
There is a model for battery energy storages as our friends mentioned. Just make sure your Matlab license support them. It doesn't appear in any Matlab with minimum add ons on it.
I am also working on HESS for lithium ion battery and super capacitor. i am looking for a book which have simulation model for HESS can any one me such type of book please