Electrophoresis study on carbon cloth loaded with LiFePO4 for integrated flexible cathodes in lithium-ion batteries.

The electrophoretic technology was used to prepare carbon cloth loaded with LiFePO4 integrated cathodes to be used in Li-ion batteries. Carbon cloth served as the negative plate in the electrophoresis tank on which LiFePO4 powder was dispersed in the electrophoresis solution deposited under a direct current electric field. Button batteries were assembled using LiFePO4-loaded carbon cloth as the cathode and their electrochemical performance was tested. When the electrophoresis solution was at pH 4 and the electrophoresis duration was 5 min, the areal loading of LiFePO4 on the carbon cloth reached 9.7 mg cm–2 and the charge-discharge specific capacity reached 120 mAh g–1. LiFePO4 could not be deposited on the carbon cloth if the pH value of the electrophoresis solution was too high or too low. The specific capacity of the battery decreased if the electrophoresis time was more than 5 min. For comparison, carbon cloth loaded with LiNiCoAlO2 and elemental sulphur was also tested. This confirmed that enhancing the conductivity of the powdered active material deposited on the carbon cloth was the key to improving the comprehensive performance of the battery.At pH > 4, nearly all hydrogen ions were attached to the LiFePO4 particles and higher amounts of charged LiFePO4 were deposited on the carbon cloth. At pH 4, the deposition amount of LiFePO4 reached its highest at 15 mg and the areal loading reached 9.7 mg cm–2.Graphical abstract: The electrophoretic technology was used to prepare carbon cloth loaded with LiFePO4 integrated cathodes to be used in Li-ion batteries. Carbon cloth served as the negative plate in the electrophoresis tank on which LiFePO4 powder was dispersed in the electrophoresis solution deposited under a direct current electric field. Button batteries were assembled using LiFePO4-loaded carbon cloth as the cathode and their electrochemical performance was tested. When the electrophoresis solution was at pH 4 and the electrophoresis duration was 5 min, the areal loading of LiFePO4 on the carbon cloth reached 9.7 mg cm–2 and the charge-discharge specific capacity reached 120 mAh g–1. LiFePO4 could not be deposited on the carbon cloth if the pH value of the electrophoresis solution was too high or too low. The specific capacity of the battery decreased if the electrophoresis time was more than 5 min. For comparison, carbon cloth loaded with LiNiCoAlO2 and elemental sulphur was also tested. This confirmed that enhancing the conductivity of the powdered active material deposited on the carbon cloth was the key to improving the comprehensive performance of the battery.At pH > 4, nearly all hydrogen ions were attached to the LiFePO4 particles and higher amounts of charged LiFePO4 were deposited on the carbon cloth. At pH 4, the deposition amount of LiFePO4 reached its highest at 15 mg and the areal loading reached 9.7 mg cm–2. [ABSTRACT FROM AUTHOR]