Carbon-coated LiFePO₄synthesized by a simple solvothermal method

Abstract

A LiFePO 4 /C composite was directly synthesized via a simple solvothermal method. Ferric nitrate nonahydrate, FeIJNO 3 ) 3 •9H 2 O, was selected as a low cost iron source in the ethanol process and glucose as the carbon source. Through SEM images, it was found that the concentration of the glucose solution has an important influence on the morphology of particles. The samples were characterized by Raman spectroscopy and TEM measurements, showing the formation of graphitic carbon, which is desirable for its contribution to the electronic conductivity. XPS analysis verified that Fe 3+ was almost completely reduced to Fe 2+ . CV (cyclic voltammetry), EIS (electrochemical impendence spectroscopy), and galvanostatic charge/discharge tests were conducted to further study the electrochemical properties of the LiFePO 4 /C composite. The results reveal that the LiFePO 4 /C composite with a rodlike shape has the highest specific capacity of 147 mA h g −1 at 0.1C, and the capacity retention remains 100% after 50 cycles.

Recycling of cathode from spent lithium iron phosphate batteries

“…The specific capacity of as synthesized LFP at applied current of 2C is around 80 mAh/g and at 5C around 50 mAh/g respectively. Further work on improving the specific capacity of as synthesized LFP is in process where we are trying to coat LFP with less carbon but more uniform carbon coating [66][67][68]. The initial charge capacity is low due to 20 % w/w of carbon in the as synthesized LFP.…”

Solid-state reaction synthesis and characterization of Mn-doped LiFePO4 cathode material

“…However, this material possesses drawbacks of low electronic conductivity (<10 -9 Scm -1 ) and poor Li + ion diffusion. In addition, its low working potential (3.4 V vs. Li/Li + ) restricts to use in high power applications, such as electric vehicles IOP Publishing doi:10.1088/1757-899X/1234/1/012029 2 [3][4][5]. Several methods can be used to tackle the drawbacks such as tailoring morphology, coating conductive carbon on primary particles and doping with some transition metal ions (e.g., Mn + , Co + , Ni + , Mg 2+ , Cr 3+ , Ti 4+ , etc.)…”