Limited Solid Solutions LiMn2−xBxO4 (Fd-3m) and Li(Ni,Mn,Co)1−zBzO2 (R-3m)

The samples of LiMn 2−x B x O 4 (0 ≤ x ≤ 2, step x = 0.1) were synthesized by gel combustion with polyvinyl alcohol. To obtain samples of Li (Ni 0.4 Mn 0.3 Co 0.3 ) 1−z B z O 2 (0 ≤ z ≤ 1, step z = 0.1), LiNi 0.4 Mn 0.3 Co 0.3 O 2 was synthesized separately by gel combustion with starch, and afterwards sintered with LiBO 2 . Based on x-ray diffraction data, the boundary compositions LiMn 1.5 B 0.5 O 4 and Li (Ni 0.4 Mn 0.3 Co 0.3 ) 0.9 B 0.1 O 2 for solid solutions with spinel and α-NaFeO 2 structures were established. The change in the elementary cell parameters of solid solutions depending on the boron content was analysed. Electrochemical testing of LiMn 1.8 B 0.2 O 4 and LiMn 1.5 B 0.5 O 4 samples was performed. Phase equilibria between the crystalline phases of the Li-Mn-B-O system under isobaric-isothermal conditions were presented.