Olivine Positive Electrodes for Li-Ion Batteries: Status and Perspectives

Abstract

Among the compounds of the olivine family, LiMPO 4 with M = Fe, Mn, Ni, or Co, only LiFePO 4 is currently used as the active element of positive electrodes in lithium-ion batteries. However, intensive research devoted to other elements of the family has recently been successful in significantly improving their electrochemical performance, so that some of them are now promising for application in the battery industry and outperform LiFePO 4 in terms of energy density, a key parameter for use in electric vehicles in particular. The purpose of this review is to acknowledge the current state of the art and the progress that has been made recently on all the elements of the family and their solid solutions. We also discuss the results from the perspective of their potential application in the industry of Li-ion batteries.The main disadvantage of olivines with respect to other cathode chemistries for lithium batteries is the lower energy density. This is evidenced in Table 1 where we have reported the gravimetric and volumetric energy densities of LFP and two other cathode materials which have also found a market place in commercial batteries for electric vehicles: the manganese spinel LiMn 2 O 4 , and "LiNiCoAl" (NCA). In terms of energy density, the winner is clearly NCA, the cathode material used by Panasonic to manufacture the batteries of Tesla cars. However, the low energy density of LFP was not an obstacle for its success for EV applications. The top-selling EV manufacturer in the world today is BYD, which makes its own batteries. Its success comes from its choice of the LFP cathode chemistry. As an example, BYD's LFP battery used by e6 taxis in Shenzen has a driving range of 200 km and can be charged to 80% in just 20 min, or 100% in only 40 min using a BYD DC fast charger. The town has 12,000 taxis which will be electric by the end of this year, and all of the 7,000,000 buses are already electric buses, 80% being BYD buses.

Mössbauer Spectroscopy of Triphylite (LiFePO4) at Low Temperatures

“…62). The observed lattice parameters a = 10.3234(3) Å, b = 6.0045(2) Å and c = 4.6915(1) Å is are in a good agreement with the previous data [1, 3,34,35] summarized also in Reference [2]. In this way, the expected structure of the investigated sample was confirmed.…”

“…Triphylite or lithium iron phosphate (LiFePO 4 , LFP) compound is frequently used as a cathode material for Li-ion batteries [1,2]. It offers some advantages, but also shows a few disadvantages when compared to the most frequently used lithium cobalt oxide (LiCoO 2 ) based batteries.…”

Sustainable Battery Materials for Next‐Generation Electrical Energy Storage

“…The drawback of current LiFePO 4 -based materials lies in their relatively low energy content and relatively high production cost, which are promisingly overcome by continuous engineering endeavors. [58]…”

First-Principles Study of the Impact of Grain Boundary Formation in the Cathode Material LiFePO4

“…These studies have provided advanced characterizations techniques for cathodes such as general methods for understanding the relation between lattice distortions and potential shifts [6]. Recent review [8] summarizes the status and perspectives of LIB cathodes based on the olivine structure, including LFP. Since LIB cathodes are made of powders, grain surfaces and interfaces come to play.…”