EPA-112-XB08

112

1,601 千元

補助及獎勵回收清除處理暨再生利用

2023/02/18

2023/11/30

呂宗昕

循環署回收基金管理會

鄭秋萍

國立臺灣大學

廢棄物管理、資源循環

磷酸鋰鐵、水熱法、磷酸鋰鐵電池回收、鋰離子電池

Lithium iron phosphate, Hydrothermal method, Lithium iron phosphate battery recycling, Lithium-ion battery

呂宗昕

02-23651428#

chlu@ntu.edu.tw

本研究提出一種水熱合成方法，降低反應溫度並減少碳排放，透過新型環保型水熱合成技術合成磷酸鋰鐵，此方法採用封閉系統反應，無廢氣排放，並促進低溫結晶，建立我國自主生產磷酸鋰鐵材料的節能環保技術。從研究結果可發現，本研究透過酸浸取回收之廢磷酸鋰鐵，並且透過本研究所開發之低溫環保型水熱合成技術，將浸取液用於再生磷酸鋰鐵，透過晶相分析，製得磷酸鋰鐵純相，而在粒徑分析中可觀測到粒徑小於1微米。從電化學測試中可發現再生磷酸鋰鐵相較廢磷酸鋰鐵擁有較良好之穩定性和動力學表現。經過50圈充放電後電容量維持93%，且庫倫效率高達97%，廢磷酸鋰鐵電容量僅剩83%且庫倫效率降至77%。再生磷酸鋰鐵在2C、5C高倍率電流下分別仍有91、55mAh/g之電容量，而廢磷酸鋰鐵無法有效充放電。將再生磷酸鋰鐵進行改質，在5C高倍率下電容量由55mAh/g提高至75mAh/g。

磷酸鋰鐵、水熱法、磷酸鋰鐵電池回收、鋰離子電池

EPA-112-XB08.pdf

3MB

2024/4/1 上午 12:00:00

This study developes a hydrothermal synthesis method tailored to lowering reaction temperatures and reducing carbon emissions. Lithium iron phosphate is synthesized through an innovative, environmentally hydrothermal synthesis technology. This approach employs a closed-system reaction, resulting in the reduction of waste gas emission and the promotion of crystallization at low temperatures. This achievement can increase the capability of our country for the production of energy-efficient and eco-friendly lithium iron phosphate materials. In this investigation, acid leaching is applied for the recovery of waste lithium iron phosphate, while the low-temperature, environmentally friendly hydrothermal synthesis technology developed by this institution is harnessed for lithium iron phosphate regeneration. Crystal phase analysis confirms the production of a high-purity lithium iron phosphate in a single phase, with particle sizes observed to be less than 1 micron. Electrochemical tests reveal that the regenerated lithium iron phosphate exhibits superior stability and kinetic performance when compared to waste lithium iron phosphate. Following 50 charge and discharge cycles, the capacity remains at 93%, accompanied by a remarkable Coulombic efficiency of 97%. In contrast, waste lithium iron phosphate batteries retain only 83% of their capacity, with Coulombic efficiency decreasing to 77%. Regenerated lithium iron phosphate maintains capacities of 91 mAh/g and 55 mAh/g under high-rate currents of 2C and 5C, respectively, while waste lithium iron phosphate fails to demonstrate effective charge and discharge capabilities. Furthermore, through the modification process, the capacity of regenerated lithium iron phosphate is enhanced from 55 mAh/g to 75 mAh/g at a high rate of 5C.

Lithium iron phosphate, Hydrothermal method, Lithium iron phosphate battery recycling, Lithium-ion battery