Transforming Materials into Practical Automotive Lithium‐Ion Batteries

Abstract

Although tremendous efforts have been devoted into research and development of materials science and engineering, chemistry, electrochemistry, and solid‐state physics in lithium‐ion batteries (LIBs) over the last 30 years, the critical technologies and applied science underneath manufacturing and processing seem very seldom reported, which is further manifested by the realization of the gap between academy and industry within recent years. In this paper, the intrinsic relationship of materials‐processing‐performance is highlighted by thoroughly reviewing the bridge effect of processing, transport, and transfer at different scales across electrode, heterogeneous thermodynamics, and kinetics during charge‐discharge cycles, the tradeoff between areal capacity and rate performance, and some practical novel electrode designs. Based on very limited open literature, the fundamental basics and sciences of the state of art production steps including slurry mixing, coating, drying, calendering, electrolyte filling, and formatting are comprehensively discussed. Through correlating with the materials design and development, the electrode compositions and structures, and the bridge effect of processing, the in‐depth understanding of the importance of individual steps and their interactions are provided to shed light on further improvement on materials and manufacturing for LIBs.

Low-Cost Tin Compounds as Seeds for the Growth of Silicon Nanowire–Graphite Composites Used in High-Performance Lithium-Ion Battery Anodes

“…SnS–SiGt can be described as micro-sized particles of SiNWs embedded in graphite. In fact, the main porosity in the electrode comes from the space between the SiGt particles that could be reduced by varying the graphite size …”

“…In fact, the main porosity in the electrode comes from the space between the SiGt particles that could be reduced by varying the graphite size. 55 In the close-up image in Figure 7b, additional nanoporosity is clearly seen. This internal nanoporosity provides enough space for silicon swelling and electrolyte access, beneficial for cycling without adding over-proportionated porosity.…”

Insights into Influencing Electrode Calendering on the Battery Performance

“…Implementing Equation (9) into Equation ( 7) led to a fit from empirical modeling of the dependency between applied line load and coating density or, respectively, coating porosity that covers the influence of mass loading, roll temperature, and coating recipe: [15] 𝜀…”

“…[3,4] However, electrode and cell manufacturing development are also critical for enhancing the energy density, and other performance parameters such as cycling stability and rate capability of LIBs. [5] Currently, the manufacturing of LIB electrodes [1,[6][7][8][9][10][11][12][13][14] involves slurry mixing, all the way to cell building and welding processes (Figure 1a). Calendering (Figure 1b) is a standard and low-cost (about 5% of the total cost) [1] process in electrode manufacturing, which can increase the cell volumetric energy density and enhance the bonding strength between the active materials/conductive carbons/binders and the current collector by reducing the porosity from 50--70% down to 20-40%.…”

Mesoporous Carbon Materials for Electrochemical Energy Storage and Conversion

“…Lithium-ion batteries (LIB) are the most widely used rechargeable batteries at present. Cathode materials such as LiCoO 2 , LiMn 2 O 4 , LiFePO 4 (LFP), and Li[Ni x Co y Mn z ]O 2 (NCM, x + y + z = 1) [100,101] are applied on different occasions. Especially, LFP and NCM batteries are the hottest candidates for electric vehicles (EV) like TESLA.…”