The unstable electrode/electrolyte interface is one of the key obstacles for practical Ah-level Li metal batteries, but an efficient approach that can construct a stable interface on both a cathode and an anode simultaneously is lacking. Herein, on the basis of a strategy for regulating electrolyte solvation chemistry, fluoroether as a destabilizer is introduced to disturb the Li + solvation sheath and weaken the interaction between Li + and carbonyl of carbonate-based solvents, which renders recrystallization of LiPO 2 F 2 from the electrolyte for concurrent surface protection on both the anode and the cathode. Decomposition of LiPO 2 F 2 forms Li 3 PO 4 and LiF, which rebuild the electrode/electrolyte interface and prevent oxidation of carbonate solvent under a high voltage of 4.6 V. Using this strategy, the Li symmetrical cell can sustain 10 mAh cm −2 Li stripping/plating for 1000 h; a 3.62 Ah pouch cell of Li/Lirich layered oxide with a N/P ratio of 2.0 and an electrolyte injection ratio of 2.49 g/Ah exhibit an ultrahigh energy density of 430 Wh kg −1 and an extended lifespan.

A Li7P3S11 glass-ceramic solid electrolyte and a core–shell S@BP2000 nanocomposite are used to fabricate all-solidstate Li–S batteries, which exhibit outstanding cycle stability and rate capabilities.

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A thermally initiated conversion method with facile fabrication procedures for Li/graphene composite anode is reported, and a 2.6 A h pouch cell employing this anode delivers a high energy density of 356 W h kg−1 and a long lifespan of 100 cycles.

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Fire safety issues hinder the large‐scale application of lithium‐ion batteries (LiBs). Here, a new type of fire‐response separators is prepared by loading the microcapsule fire extinguishing agent on the surface of the separator. The shell of the microcapsule will break automatically at a certain temperature and release the fire extinguishing agent when thermal runaway of LiBs occurs, which can quickly absorb heat through endothermic reaction and ensure LiBs will not burn or explode. The porosity of fire‐response separator is 53.6%, the electrolyte uptake is 132% and the ionic conductivity is 1.00 mS cm‐1. The initial specific capacity is 2643 mAh g‐1 at 4°C and the capacity retention rate is 93% after 200 cycles for NCM523 battery based fire‐response separator. The temperature of LiBs based on the fire‐response separator can automatically drop to room temperature in 20 seconds, which ensures the safety of other adjacent LiBs. This work proposes a new active protection concept to solve the safety problem of LiBs.

Lithium metal batteries have been considered as one of the most promising next‐generation power‐support devices due to their high specific energy and output voltage. However, the uncontrollable side‐reaction and lithium dendrite growth lead to the limited serving life and hinder the practical application of lithium metal batteries. Here, a tri‐monomer copolymerized gel polymer electrolyte (TGPE) with a cross‐linked reticulation structure was prepared by introducing a cross‐linker (polyurethane group) into the acrylate‐based in situ polymerization system. The soft segment of polyurethane in TGPE enables the far migration of lithium ions, and the ‐NH forms hydrogen bonds in the hard segment to build a stable cross‐linked framework. This system hinders anion migration and leads to a high Li+ migration number ( = 0.65), which achieves uniform lithium deposition and effectively inhibits lithium dendrite growth. As a result, the assembled symmetric cell shows robust reversibility over 5500 h at a current density of 1 mA cm−2. The LFP¦¦TGPE¦¦Li cell has a capacity retention of 89.8% after cycling 800 times at a rate of 1C. In summary, in situ polymerization of TGPE electrolytes is expected to be a candidate material for high‐energy‐density lithium metal batteries.

LiNi0.5Co0.2Mn0.3O2 (NCM523) has become one of the most popular cathode materials for current lithium-ion batteries due to its high-energy density and cost performance. However, the rapid capacity fading of NCM severely hinders its development and applications. Here, the single crystal NCM523 materials under different degradation states are characterized using scanning transmission electron microscopy (STEM). Then we developed a neural network model with a two-sequential attention block to recognize the crystal structure and locate defects in STEM images. The number of point defects in NCM523 is observed to experience a trend of increasing first and then decreasing in the degradation process. The space between the transition metal columns shrinks obviously, inducing dramatic capacity decay. This analysis sheds light on the defect evolution and chemical transformation correlated with layered material degradation. It also provides interesting hints for researchers to regenerate the electrochemical capacity and design better battery materials with longer life.