Polyhedral LiNi_0.5Mn_1.5O₄ with excellent electrochemical properties for lithium-ion batteries

Abstract

Polyhedral LiNi0.5Mn1.5O4 exhibiting superior rate and cyclability represents the first experimental evidence for lattice-plane anisotropy.

Polyhedral ordered LiNi0.5Mn1.5O4 spinel with excellent electrochemical properties in extreme conditions

“…1(d). Comparing to our previous result of Fd-3m, [19] the same bands at 639 (A 1g ), 495 (F ð2Þ 2g ) and 406 cm À1 (E 1g ) can be assigned to the symmetric MneO stretching mode and the Ni 2þ -O stretching mode in this structure, respectively. While an extra peak at 218 cm À1 and the splitting of F ð3Þ 2g band at 606 and 590 cm À1 , considering to the "fingerprint" peaks in Raman spectroscopy for P4 3 32 phase, [20] are obviously observed.…”

“…On the other hand, octahedral ordered LNMO (see in Fig. S1) can be also obtained via annealing the disordered LNMO, which can be synthesized by a controllable method [19]. It means that almost all the electrochemical-property-effecting factors, such as: synthetic method, starting materials, degree of purity, effects of impurity, crystal structure or crystalline phase, grain size, surface morphology, and so on, can be kept consistently except their surface planes.…”

“…The polyhedral ordered LiNi 0.5 Mn 1.5 O 4 spinel (denoted as LNMO-P) was obtained based on our previous report [19]. All chemicals were of analytical grade and obtained from Aladdin.…”

“…Recently, Manthiram [17,18] and co-workers have found that surface planes have an important effect on the electrochemical properties of ordered LiNi 0.5 Mn 1.5 O 4 cathode. Interestingly, our group [19] have also achieved a disordered LiNi 0.5 Mn 1.5 O 4 material with a good compatibility between energy/power density and cycle life without sacrificing any other properties through synthesizing a chamfered polyhedral structure. This unique structure can not only provides some surface facets favoring of Li-ions diffusion, but also alleviate the lattice strain coming from phase transitions during (de)intercalation process.…”

Synthesis of high-voltage spinel LiNi0.5Mn1.5O4 material for lithium-ion batteries by a metal-cholate supramolecular hydrogel as precursor

“…Afterward, the obtained hydrogel was transferred to a vacuum oven and dried overnight at 90°C. The dried precursor was calcined at 500°C for 5 h, ground, and further heated up to 850°C and maintained for 10 h [25]. The as-obtained samples with different amount of cholic acid were labeled as LNMO-1, LNMO-2, LNMO-3, and LNMO-4, respectively.…”