Conspectus
All-solid-state
lithium batteries have received considerable attention
in recent years with the ever-growing demand for efficient and safe
energy storage technologies. However, key issues remain unsolved and
hinder full-scale commercialization of all-solid-state lithium batteries.
Previously, most discussion only focused on how to achieve high energy
density from the theoretical perspective. Herein, we analyze the real
cases of different kinds of all-solid-state lithium batteries with
high energy density to understand the current status, including all-solid-state
lithium-ion batteries, all-solid-state lithium metal batteries, and
all-solid-state lithium–sulfur batteries. First, we propose
a general calculation method to visually compare the above battery
systems partly due to no normative parameters for solid-state batteries.
After then, we discuss and interpret the key parameters and current
situation of all-solid-state lithium batteries. Through the summary
and analysis of the frontier, one can find that, although some breakthrough
has been made in energy density and areal capacity for solid-state
batteries, there are still many aspects to be improved such as power
density and rate performance. Therefore, in response to the challenges,
we propose possible directions for future development, including the
ways to prepare different kinds of solid electrolyte films to reduce
the proportion of inactive substances in the cell. The advantages
and disadvantages are discussed about three typical solid-state electrolyte
films (inorganic solid electrolyte, solid polymer electrolyte, and
composite solid electrolyte). In addition, potential candidate anodes
with high capacity and cathodes with high voltage and/or high capacity
are also discussed in details. The combination of lithium metal anodes
with ultrahigh capacity and cathodes with both high capacity and high
voltage is the current mainstream direction. However, the interface
problems have become the most pressing factor on the application.
Therefore, we introduce the origin of interfaces and interphases and
discuss how to build a stable electrode/solid electrolyte interface.
One thing is clear that artificial solid electrolyte interphases and
composite solid electrolytes are effective to obtain stable anode/solid
electrolyte interfaces, which can prevent lithium from constantly
reacting with solid electrolytes, ensure the uniform lithium deposition
and prevent the formation of lithium dendrites. For the cathode/solid
electrolyte interface, reasonable composite cathodes, multilayer design,
and composite solid electrolytes can optimize the electrode and interface
for stable cycles at high voltages and high current densities. Furthermore,
the contribution of high-throughput computations and machine learning
is introduced in accelerating materials screening and development.
Among them, progress has been made in solid electrolytes and artificial
solid electrolyte interphases through materials genome engineering
and machine learning. Finally, we provide some out...