激光蚀刻负极片对锂离子电池性能的影响

Effect of laser etched anode electrode on the performance of lithium-ion batteries

厚电极技术可以有效提升锂离子电池中正极及负极活性物质的占比,降低隔膜及集流体非活性物质的占比,进而有效提升锂离子电池的能量密度。但锂离子电池电极厚度的增加会导致电荷(电子及离子)传输距离及阻抗增加、负极片动力学恶化,进而严重影响锂离子电池循环寿命。通过激光蚀刻后的负极片,可以增加极片表面的孔隙,并增加石墨颗粒表面的锂离子脱嵌通道,有效改善负极片的动力学性能。与辊压后的负极片形成的锂离子电池相比,激光蚀刻负极片形成的锂离子电池在常温下的循环寿命提升了87%,在45℃下的循环寿命提升了37%。

Thick electrode design strategies can effectively increase the active material loading(cathode and anode)and decrease the inactive component ratio(current collector and separator)of lithium-ion batteries,thereby leading to increased battery energy density.However,increasing the electrode thickness of lithium-ion battery will inevitably result in a proportional increase in charge(electrons and ions)transport distance and transport resistance,and cause sluggish kinetics for anode electrode,which may have bad effect on the cycle life of lithium-ion battery.Electrode surface porosity and passway for lithium-ion transport increases by laser etching,which improves kinetics of anode electrode.Compared with the base lithium-ion battery with pristine anode electrode,lithium-ion battery assembled with the laser etched anode electrode reveals prolonged cycle life of 87%at room temperature and 37%at 45 degrees.