High capacity and good cycling stability of the electrode materials are the key points to develop high-performance lithium ion battery. Based on the latest research over the world, especilly from our group, in this paper we summarized the progress in chemical lithiation and electroactivity of nanomaterials. Firstly, we introduced the preparation of high capacity nanomaterials (molybdenum oxide, vanadium oxides, selenium hydrates, etc) and the chemical problems in lithiation process. Then we summed up the progress in assembly, chemical lithiation and electroactivity of single nanowire devices and nanowire lithium ion battery. Finally, we pointed out that assembly of single nanowire (nanobelts, nanotubes, etc.) device, in situ probe of lithium ion transport, design and construction of ordered array and complex structure, investigation of lithiation mechanism, electrostatic coupling, interface interaction, etc. are effective methods to deeper exploration of the relationship between chemical lithiation and electroactivity of nanomaterials and main directions of nanoscale lithium ion battery research field.