Small things make big deal: Powerful binders of lithium batteries and post-lithium batteries

Lithium-ion batteries are important energy storage devices and power sources for electric vehicles (EV) and hybrid electric vehicles (HEV). Electrodes in lithium-ion batteries consist of electrochemical-active materials, conductive agent and binder polymers. Binder works like a neural network connecting each part of electrode system and performs two major functions: the first one is to cohere active materials and conducting additive agent into integrity, as well as bind the matrix laminate and the current collector together. The second one is to build electron and ion circuits to guarantee the effective lithiation and delithiation. Therefore, binder, with minor content in electrode system, not only guarantees the integrity of electrode but also has enormous impacts on the stability and cyclic performance of electrodes. In this work, state of marketing and working mechanism of binder in electrode are introduced, conventional and multifunctional binders with rational tailor in latest years are reviewed, and the battery failure related to binders along with the maintaining challenges in battery field are discussed. What's more, a general conclusion and instructive directions of binders for future research are presented.