Structural and conductivity studies on LiNiPO4 synthesized by the polyol method

Studies of thermal decomposition kinetics and temperature dependence of thermodynamic functions of the new precursor LiNiPO4·3H2O for the synthesis of olivine LiNiPO4

“…The XRD patterns of the calcined products at 400 and 500°C illustrate low intensity suggesting the low crystallinity, while the calcined products at 600, 700 and 800°C are of higher crystallinity. Thus, the anhydrous LiNiPO 4 can be produced at 600°C, which is a lower temperature and in shorter time than that reported in the literatures [14,21,22] Fig. 4.…”

“…Minakshi et al [14] synthesized LiNiPO 4 by solid-state reaction between Li 2 CO 3 , NiO and NH 4 H 2 PO 4 , and the final product was obtained after preheat treatment at 375°C (12 h) and calcined at 800°C for 24 h. Later in 2012, Prabu et al [21] reported the synthesis of LiNiPO 4 by Pechini-type polymerizable precursor method, and the crystalline LiNiPO 4 was obtained after calcination at 800°C for 8 h. Additionally, Karthickprabhu et al [22] reported the synthetic method of LiNiPO 4 by the polyol method using 1,2 propanediol and ethylene glycol as a medium, followed by the calcination at 650°C. Based on our previous work, Co 3x Ni 3-3x (PO 4 ) 2, 0 B x B 1, was successfully synthesized with high surface area via the hydrate precursors obtained from low temperature (50°C) [23].…”

“…Based on our previous work, Co 3x Ni 3-3x (PO 4 ) 2, 0 B x B 1, was successfully synthesized with high surface area via the hydrate precursors obtained from low temperature (50°C) [23]. In this work, the synthesis of LiNiPO 4 was carried out via the new precursor obtained from the simple wet chemical reaction at 50°C for 24 h followed by the calcination at 600°C for 6 h in air atmosphere, which is simpler than that reported in the literatures [14,21,22]. The nonisothermal decomposition kinetics of LiNiPO 4 Á3H 2 O was subsequently studied according to Ozawa-Flynn-Wall (OFW) and Kissinger-Akahira-Sunose (KAS) methods.…”

Polyanionic Compounds as Cathode Materials

“…Synthetic methods include solid state reaction with a final heat treatment at 775 C for 48 h in argon [166][167][168][169][170][171][172][173], ball milling mixing carbon with the precursors [174], freeze-drying process assisted by formic acid [175], polyvinyl-pyrrolidone assisted sol-gel route [176], precipitation method [177], Pechini method [178,179], polyol method using 1,2 propanediol and ethylene glycol [180], thin film deposition [181]. LCP powders were prepared by an original solid-state synthesis procedure based on the use of an alternative cobaltcontaining precursor CoNH 4 PO 4 and a lithium excess synthesis with carbon black as temporal dispersing agent, later eliminated as CO 2 [181].…”

High Voltage Cathode Materials

“…Synthetic methods include solid state reaction with a final heat treatment at 775°C for 48 h in argon [145,[147][148][149][150][151][152][153][154], ball milling mixing carbon with the precursors [155], freeze-drying process assisted by formic acid [156], polyvinyl-pyrrolidone assisted sol-gel route [157], precipitation method [158], Pechini method [159,160], polyol method using 1,2 propanediol and ethylene glycol [161], thin film deposition [158]. LCP powders were prepared by an original solid-state synthesis procedure based on the use of an alternative cobalt-containing precursor CoNH 4 PO 4 and a lithium excess synthesis with carbon black as temporal dispersing agent, later eliminated as CO 2 [162].…”