Low temperature process modified MCMB for lithium ion batteries

• We reduce the production of carbonization temperature to make it easier.
• Comparison with natural graphite powder that the low temperature MCMB can resistance to high current charge and discharge.
• The modified samples by quinoline solubles (QS) can increase the charging capacity and discharge capacity.

The negative electrode of a lithium-ion battery should have the characteristics of large charge capacity, excellent charge and discharge cycle, steady discharge voltage, low irreversible charge capacity, and stable electrolyte. Natural graphite and mesocarbon microbeads (MCMB) are the most common materials used for the negative electrodes of such batteries. This study examines the effect of the use of homemade non-modified MCMB (HMM), modified MCMB (HMMQ), and natural graphite (NG) to produce electrodes on the batteries' high current charge–discharge behavior. In this experiment, the charge–discharge results showed that the voltage plateaus of HMM and HMMQ sloped due to short-range structural order, which enabled the intercalation and deintercalation of lithium ions to occur at different voltages. When HMMQ was charging and discharging high current at a rate of 2 C, the battery's charge capacity reached 160 mAh·g− 1 and the coulometric efficiency exceeded 96%. Following the start of charging and discharging, a stable solid electrolyte interface (SEI) layer formed on HMMQ. The charge capacity of HMMQ was approximately 167 mAh·g− 1 after 100 charge–discharge cycles at 1 C, and the cycles were stable. According to FTIR analysis, the content of the SEI layer produced within HMMQ consisted of Li2CO3 and (CH2OCOLi)2, and was stable, non-soluble, and passive. Negative electrodes made using modified material displayed good stability throughout many cycles when charging and discharging at a high current.