Details

Autor(en) / Beteiligte

• Han, Zhen-Ji
• Yabuuchi, Naoaki
• Shimomura, Keiji
• Murase, Masahiro
• Yui, Hiroharu
• Komaba, Shinichi

Titel

High-capacity Si–graphite composite electrodes with a self-formed porous structure by a partially neutralized polyacrylate for Li-ion batteries

Ist Teil von

• Energy & environmental science, 2012-10, Vol.5 (10), p.9014-9020

Erscheinungsjahr

2012

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• NaOH-neutralized poly(acrylic acid) is examined as a binder for Si-based negative electrodes in rechargeable Li-ion batteries. To better understand the influence of polymer binder characteristics, the impact of neutralization degree (ND) of poly(acrylic acid) (PAH) on electrode performance of a Si-graphite composite is studied. The electrode performance of the Si-based composites is remarkably improved by appropriate neutralization of PAH because the NDs highly influence rheological properties of a slurry and thus the electrode morphology, such as porosity. It is found that 80% neutralized PAH provides the moderate porous structure inside the composite electrode with 10 wt% binder content because of a unique rheological property during the drying process after casting the slurry onto a current collector. The self-formed porous structure by the partially neutralized PAH is beneficial to buffer volume expansion caused by lithiation of Si. Therefore, an excellent capacity retention for a 100 cycle test with a high reversible capacity of approximately 1000 mA h g super(-1) is achieved with the 80% neutralized PAH as a binder for Si-based composite electrodes.