Energy Density Lithium-ion Batteries Research Articles

Elucidating in-situ heat generation of LiFePO4 semi-solid lithium slurry battery under specific cycling protocols

Semi-solid lithium slurry battery combines the advantages of the high energy density of lithium-ion battery and the flowability of flow battery electrodes and has attracted attention in energy storage. Elucidating the heat generation during cycling is crucial for evaluating the safety. However, there is a relative lack of research in this field of semi-solid lithium slurry battery. Herein, the heat generation of lithium iron phosphate (LiFePO4) semi-solid lithium slurry battery during cycling under specific cycling protocols is investigated in this work. The results show that the battery has lower heat generation when cycling at an ambient temperature of 35–50 ℃ and a charging cutoff voltage below 4.0 V, meanwhile, it maintains considerable capacity. However, when the charging cutoff voltage exceeds 4.4 V, the cyclic heat generation of the battery increases significantly, and the capacity attenuates significantly. Meanwhile, the classical equation for calculating battery heat generation of lithium-ion battery is no longer reliable. This is mainly because the electrolyte content of the semi-solid lithium slurry battery is too high (over 80 %), and at high charging cutoff voltage, the side decomposition reactions of the electrolyte increase significantly. Subsequent characterization of electrode materials also confirms this inference. This study can provide a clearer understanding of the safety of semi-solid lithium slurry battery and has guiding implications for industrial applications.

Electrochemical performance of lithium-ion batteries with two-layer gradient electrode architectures

Thick electrodes whose active materials have high areal density may improve the energy densities of lithium-ion batteries. However, the weakened rate abilities and cycle lifetimes of such electrodes significantly limit their practical applications. In this study, a modified two-dimensional model was built to evaluate the influence of the electrode structure on the lithiation process. Gradient electrodes with different particle sizes along the thickness direction are designed and fabricated via a two-layer coating process. The gradient design in the thickness direction is confirmed by three-dimensional digital microscopy, energy-dispersive spectroscopy, X-ray diffraction, and scanning electron microscopy. Galvanostatic charge/discharge cycling tests and electrochemical impedance spectroscopy are performed to investigate the electrochemical properties of the fabricated gradient electrodes. The simulation results indicate that the gradient electrode structure can enhance the utilization of electrode particles on the current collector side and alleviate the nonuniformity of the solid-phase Li concentration along the thickness direction. High electrochemical performance and long-term cycling stability of the designed gradient electrodes are verified by electrochemical test. The gradient structure fabricated via multi-layer coating processes can be used to improve the electrochemical performance of thick electrodes.

An Electrolyte with Less Space-Occupying Diluent at Cathode Inner Helmholtz Plane for Stable 4.6 V Lithium-Ion Batteries.

Reasonably elevating the working voltage (≥4.4 V vs. Li/Li+ ) of the cathode is one of the efficient approaches to maximize the energy density of lithium-ion batteries (LIBs). As a preferred partner for high-voltage LIB systems, localized high-concentration electrolyte (LHCE), characterized by a stronger Li solvation structure, less free solvent, and robust electrode/electrolyte interphase has attracted much attention in academic circles. Herein, we systematically studied the role of the diluent in LHCE on the formation of the cathode electrolyte interphase (CEI) and elucidated that the existing anion-diluent pairing in the inner Helmholtz plane (IHP) results in an uneven CEI and subsequent battery degradation under high voltage. A m-fluorotoluene (mFT) diluent was further employed in the LHCE containing lithium difluoro(oxalato)borate (LiDFOB) to facilitate a uniform and rich-anion-derived CEI, since the weaker interaction of HmFT -BDFOB - , as compared to the HHhydrofluoroether -BDFOB - , reduces the influence of mFT in IHP or initial CEI formation. Consequently, the mFT-dominated LHCE propels the high-voltage performance of LIBs one step forward, endowing a 4.6 V-class 1.2-Ah graphite||LiNi0.8 Co0.1 Mn0.1 O2 pouch cells a 90.4 % capacity retention after 130 cycles. Our study thus describes a new index affecting the CEI formation and proposes novel strategies to deeply optimize the high-voltage LIBs.

10 μm-Level TiNb2 O7 Secondary Particles for Fast-Charging Lithium-Ion Batteries.

TiNb2 O7 with Wadsley-Roth phase delivers double theoretical specific capacity and similar working potential in comparison to spinel Li4 Ti5 O12 , the commercial high-rate anode material, and thus can enable much higher energy density of lithium-ion batteries. However, the inter-particle resistance within the high-mass-loading TiNb2 O7 electrode would impede the capacity release for practical application, especially under fast-charging conditions. Herein, 10-20 μm-size carbon-coated TiNb2 O7 secondary particle (SP-TiNb2 O7 ) consisting of initial micro-scale TiNb2 O7 particles (MP-TiNb2 O7 ) was fabricated. The high crystallinity of active material could enable fast-charge diffusion and electrochemical reaction rate within particles, and the small number of stacking layers of SP-TiNb2 O7 could reduce the large inter-particle resistance that regular particle electrode often possess and achieve high compaction density of electrodes with high mass loading. The investigation on materials structure and electrochemical reaction kinetics verified the advances of the as-fabricated SP-TiNb2 O7 in achieving superior electrochemical performance. The SP-TiNb2 O7 exhibited high reversible capacity of 292.7 mAh g-1 in the potential range of 1-3 V (Li+ /Li) at 0.1 C, delivering high-capacity release of 94.3 %, and high capacity retention of 86 % at 0.5 C for 250 cycles in half cell configuration. Particularly, the advances of such an anode were verified in practical 5 Ah-level laminated full pouch cell. The as-assembled LiFePO4 ||TiNb2 O7 full cell exhibited a high capacity of 5.08 Ah at high charging rate of 6 C (77.9 % of that at 0.2 C of 6.52 Ah), as well as an ultralow capacity decay rate of 0.0352 % for 250 cycles at 1 C, suggesting the great potential for practical fast-charging lithium-ion batteries.

Trends in the Gravimetric and Volumetric Energy Densities of Lithium-Ion Batteries over the Past Decade

Trends in the Gravimetric and Volumetric Energy Densities of Lithium-Ion Batteries over the Past Decade

Ultraviolet-thermal coupling cross-linked fabricate polymer/ceramic composite solid electrolyte for room temperature quasi solid state lithium ion batteries

Polymer-based electrolyte, as a key component of lithium ion solid state battery, has good adaptability to lithium metal anode, and has received extensive attention in recent years. However, the low conductivity, limited thermal stability and poor mechanical strength of polymer-based solid electrolytes restricting its commercial application. Herein, We reveal experimentally that the Polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP)/Li1.3Al0.3Ti1.7(PO4)3 (LATP) composite solid electrolyte can be prepared by means of ultraviolet and thermal coupling curing (UV-TC) process, and the electrolyte film has better electrochemical performance than that prepared by means of thermal curing (TC) process. Therefore, the carefully designed electrolyte film is efficiently prepared by UV-TC curing process to improve the specific capacity (152.34 mAhg−1), the rate performance (89.04 mAhg−1 at 1 C) and good cycle performance (92.3 % retention rate in 100 cycles at 0.1 C) at room temperature for Li||PVDF-HFP/LATP||LFP solid state battery. The ionic conductivity of the solid electrolyte film prepared by the UV-TC method (4.3 × 10−4 S cm−1) is more encouraging than that of the TC method (9.2 × 10−5 S cm−1). This work shows that the polymer/ceramic composite solid electrolyte films (CSEs) prepared by simple and efficient UV-TC method has great prospects in realizing high energy density and high safety room temperature quasi solid state lithium ion batteries.

A computational analysis of effects of electrode thickness on the energy density of lithium-ion batteries

Elevated energy density is a prime requirement for many lithium-ion battery (LIB) applications, including electric vehicles (EVs). At the cell level, the enhanced energy density of LIBs is achievable by designing thicker electrodes, which decreases the weight of the inactive materials. This work proposed a reduced order electrochemical model (ROEM), which is an extended single particle model (extended SPM), by incorporating the existing order reduction techniques of Pseudo-Two-Dimensional (P2D) model. The proposed model was used to predict the energy density values of a nickel cobalt manganese (NCM) cell with respect to the cathode thickness. The validation of the model was performed by using MATLAB at 0.05C, 1C, 2C, 3C and 5C rates by comparing the simulation results with the experimental data obtained from the Stanford Energy Control Laboratory. The verified model was then used to simulate the effect of varying thicknesses of the cathode on energy density of the NCM cell at C/5, C/2, 1C, and 2C rates of discharge. The simulation results illustrate that increasing the cathode thickness has a profound positive impact on the energy density of the cell. The prediction of the model demonstrates a total of around 20 % increase in energy density for the increment of cathode thickness from 75 μm to 600 μm. The proposed model can replicate energy density for thicker electrodes up to 2C rate reasonably correctly. However, the incorporation of thermal characteristics and other influential parameters of LIB cells into the proposed model can yield a better prediction of energy density of thicker electrodes at higher C-rates, which is recommended for further study.

Clarifying the limiting factor of material utilization in thick electrodes of lithium-ion batteries

Improving the energy density of lithium-ion batteries is a goal pursued in state-of-the-art batteries, and the use of thick electrodes with high active material loading densities is one of the most effective and direct methods. Most studies indicate that the hindrance to the practical application of thick electrodes is mainly attributed to the slow charge kinetics, resulting in very low utilization of active materials. Here, this work shows that the thermodynamic properties of the electrode material also have a significant impact on the electrode reaction behavior. When the equilibrium potential of the electrode material has a strong dependence on the state of charge, it promotes the uniform reaction of the electrode active material. By simulating the full battery under low and high load conditions, the reaction behavior of the thin electrodes is dominated by the equilibrium potential curve. However, the reaction behavior of thick electrodes is regulated by both kinetics and thermodynamics and depends on the strength of the relationship between these two properties. Meanwhile, the graphite anode limits the release of the full battery capacity to a greater extent. This work points out a new direction for the practical development and application of thick electrodes.

Opportunities and Challenges of Layered Lithium-Rich Manganese-Based Cathode Materials for High Energy Density Lithium-Ion Batteries

Opportunities and Challenges of Layered Lithium-Rich Manganese-Based Cathode Materials for High Energy Density Lithium-Ion Batteries

Intergranular Shielding for Ultrafine-Grained Mo-Doped Ni-Rich Li[Ni0.96 Co0.04 ]O2 Cathode for Li-Ion Batteries with High Energy Density and Long Life.

Deploying Ni-enriched (Ni≥95 %) layered cathodes for high energy-density lithium-ion batteries (LIBs) requires resolving a series of technical challenges. Among them, the structural weaknesses of the cathode, vigorous reactivity of the labile Ni4+ ion species, gas evolution and associated cell swelling, and thermal instability issues are critical obstacles that must be solved. Herein, we propose an intuitive strategy that can effectively ameliorate the degradation of an extremely high-Ni-layered cathode, the construction of ultrafine-scale microstructure and subsequent intergranular shielding of grains. The formation of ultrafine grains in the Ni-enriched Li[Ni0.96 Co0.04 ]O2 (NC96) cathode, achieved by impeding particle coarsening during cathode calcination, noticeably improved the mechanical durability and electrochemical performance of the cathode. However, the buildup of the strain-resistant microstructure in Mo-doped NC96 concurrently increased the cathode-electrolyte contact area at the secondary particle surface, which adversely accelerated parasitic reactions with the electrolyte. The intergranular protection of the refined microstructure resolved the remaining chemical instability of the Mo-doped NC96 cathode by forming an F-induced coating layer, effectively alleviating structural degradation and gas generation, thereby extending the battery's lifespan. The proposed strategies synergistically improved the structural and chemical durability of the NC96 cathode, satisfying the energy density, life cycle performance, and safety requirements for next-generation LIBs.

Boosting the Cycle Performance of Iron Trifluoride Based Solid State Batteries at Elevated Temperatures by Engineering the Cathode Solid Electrolyte Interface.

Iron trifluoride (FeF3) is attracting tremendous interest due to its lower cost and the possibility to enable higher energy density in lithium-ion batteries. However, its cycle performance deteriorates rapidly in less than 50 cycles at elevated temperatures due to cracking of the unstable cathode solid electrolyte interface (CEI) followed by active materials dissolution in liquid electrolyte. Herein, by engineering the salt composition, the Fe3O4-type CEI with the doping of boron (B) atoms in a polymer electrolyte at 60°C is successfully stabilized. The cycle life of the well-designed FeF3-based composite cathode exceeds an unprecedented 1000 cycles and utilizes up to 70% of its theoretical capacities. Advanced electron microscopy combined with density functional theory (DFT) calculations reveal that the B in lithium salt migrates into the cathode and promotes the formation of an elastic and mechanic robust boron-contained CEI (BOR-CEI) during cycling, by which the durability of the CEI to frequent cyclic large volume changes is significantly enhanced. To this end, the notorious active materials dissolution is largely prohibited, resulting in a superior cycle life. The results suggest that engineering the CEI such as tuning its composition is a viable approach to achieving FeF3 cathode-based batteries with enhanced performance.

One thousandth of quaternity slurry additive enables one thousand cycle of 5V LNMO cathode

5 V high voltage LiNi0.5Mn1.5O4 (LNMO) is one of the most promising cathode candidates for high energy density lithium-ion batteries. However, the electrochemical performance of high voltage LNMO is significantly affected by the interfacial compatibility between cathode and electrolyte. High voltage leads to decomposition of electrolyte at the cathode-electrolyte interface (CEI), consuming electrolyte and forming an uneven, unstable, and unprotected CEI, and hindering Li+ diffusion and reducing electrochemical efficiency. At the same time, along with the dissolution of transition metals and irreversible crystal structure damage over cycles, its electrochemical performance is seriously impaired. To solve these problems, it is proposed to pre-form a stable passivation layer on the LNMO surface using tiny amount of quaternity slurry additive of potassium-nonafluoro-1-butanesulfonate (KPBS). The K+ in KPBS assists construction of uniform and stable electric field at the cathode particle surface together with the Li+, which induces uniform deposition of the CEI. The lithium-ion diffusion at the interface is accelerated due to existence of rich phase boundaries between KF and LiF species within the CEI. The sulfonic acid group of KPBS is capable of inhibiting transition metal dissolution via coordination boding with Ni/Mn cations. The nona fluoro butyl structure improves the interface compatibility with the poly(vinylidene difluoride) (PVDF) binder to enhance the structure robustness of the electrode. The quadruple effects exercised by the KPBS enable the LNMO almost no capacity decay after 1000 cycles at 1C and 5 V. This work has a great potential to boost significant advance of the high energy density lithium-ion battery technology.

Defects go green: using defects in nanomaterials for renewable energy and environmental sustainability

Induction of point defects in nanomaterials can bestow upon them entirely new physics or augment their pre-existing physical properties, thereby expanding their potential use in green energy technology. Predicting structure-property relationships for defects a priori is challenging, and developing methods for precise control of defect type, density, or structural distribution during synthesis is an even more formidable task. Hence, tuning the defect structure to tailor nanomaterials for enhanced device performance remains an underutilized tool in materials design. We review here the state of nanomaterial design through the lens of computational prediction of defect properties for green energy technology, and synthesis methods to control defect formation for optimal performance. We illustrate the efficacy of defect-focused approaches for refining nanomaterial physics by describing several specific applications where these techniques hold potential. Most notably, we focus on quantum dots for reabsorption-free solar windows and net-zero emission buildings, oxide cathodes for high energy density lithium-ion batteries and electric vehicles, and transition metal dichalcogenides for electrocatalytic green hydrogen production and carbon-free fuels.

High-pressure and high-temperature synthesis of black phosphorus-graphite anode material for lithium-ion batteries

Phosphorus-based materials with a high theoretical specific capacity and a fast charge-discharge rate are considered as promising anode materials for high energy density lithium-ion batteries (LIBs). Red phosphorus (RP) and black phosphorus (BP) are two main allotropes to be used as anode materials. However, huge volume expansion during charge-discharge processes hinders the application of RP and BP in LIBs. Composites of phosphorus and carbon-based materials have been extensively fabricated to withstand volume expansion of phosphorus and improve cycle performance. Here, composites of BP and graphite (BP-G) with three P-G mass ratios (8 : 2, 7 : 3, and 6 : 4) have been synthesized by a facile and scalable high-pressure and high-temperature (HPHT) method using RP and graphite composites (RP-G) prepared by ball milling as precursors. Their microstructure and bonding configurations have been analyzed by various characterization techniques. Among three RP-G composites, 7RP-3G exhibits the most excellent cycling stability, a high reversible capacity of 1331 mAh/g after 200 cycles at a current density of 0.78 A/g. However, RP-G composites show poor stability at high current densities. Among three BP-G composites, 6BP-4G shows the best cycle stability at high current densities, a reversible capacity of 634.6 mAh/g after 500 cycles at a current density of 2.6 A/g. Although, the reversible specific capacities of BP-G composites after long cycles are lower than those of RP-G, BP-G composites show more stable cycle performance than RP-G, especially at high current densities. The present work illustrates a direct and facile method to synthesize BP-G composites, and sheds light to explore new synthetic route of BP-based composites.

Li4Ti5O12-TiO2 composite coating layer enabling LiNi0.8Co0.1Mn0.1O2 electrodes with superior cycling performance

Nickel-rich LiNi0.8Co0.1Mn0.1O2 (NCM811) materials are considered to be one of the cathode candidate materials for high energy density lithium-ion batteries (LIBs), but its electrochemical instability caused by electrodes to electrolyte interface degradation needs to be overcome. Surface coatings can effectively solve this problem. However, traditional coating techniques cover particles rather than electrodes to protect a broader area. Herein, for a more precise coating, a nanoscale Li4Ti5O12-TiO2 composite coating layer (LTOTO) is directly sputtered onto the NCM811 electrodes surface. The LTOTO has superior electronic conductivity compare to Li4Ti5O12. Lithium ions and electrons can diffuse and distribute more uniformly owing to the LTOTO coating on NCM811 electrode. For NCM811 electrodes, the LTOTO coating layer serves as the cathode-electrolyte interface (CEI) within the cycling potential range. Because of its robust structure and strong chemical inertness, LTOTO may successfully shield NCM811 electrodes from electrolyte reactions. The rate performance of NCM811 electrodes is significantly enhanced after Li4Ti5O12-TiO2 coating at 5C (149.74 mAh/g). The capacity retention of NCM811/LTOTO-3 electrode at 1C is 93.2 % at the 100th cycle, which is 13.3 % higher than that of the pristine NCM811 electrodes.

ACGNet: An interpretable attention crystal graph neural network for accurate oxidation potential prediction

LiNixCoyMn1-x-yO2 (NCM) is one of the most critical cathode materials for high energy density lithium-ion batteries in electric vehicle applications. Nevertheless, capacity degradation and long-term cycle instability due to the aging of cathode/electrolyte interfaces remain significant challenges for NCM materials. Various surface stabilization techniques, including doping and coating, can be employed for NCM modifications. Traditionally, new coating materials are identified by chemical intuition or trial-and-error synthesis, which hinders the discovery speed of high-performance coating materials. A novel neural network model named Attention Graph Convolutional Neural Network (ACGNet) has been developed to predict crystals’ electrochemical stability windows from atom and bonding features and exhibits remarkable predictive performance with a mean absolute error of 0.586 V. Then, the developed model is utilized to conduct high-throughput screening of 13,943 candidate compounds for their coating potential. Among the candidates, LiPO3 exhibits prominent potential as a coating material due to its high oxidation voltage and low preparation cost. The subsequent battery assembly experiment and electrochemical characterization reveal that the incorporation of LiPO3 significantly enhances the cycle stability of NCM batteries. In summary, our model exhibits exceptional accuracy in predicting material properties and serves as a compelling example for machine learning applications in battery materials.

The Effect of Different Amounts of Conductive Carbon Material on the Electrochemical Performance of the LiFePO4 Cathode in Li-Ion Batteries

LiFePO4 (LFP) has undergone extensive research and is a promising cathode material for Li-ion batteries. The high interest is due to its low raw material cost, good electrochemical stability, and high-capacity retention. However, poor electronic conductivity and a low Li+ diffusion rate decrease its electrochemical reactivity, especially at fast charge/discharge rates. In this work, the volumetric energy density of lithium-ion batteries is successfully increased by using different amounts of conductive carbon (Super P) in the active material content. The particle size and morphology of the electrode material samples are studied using field emission scanning electron microscopy and dynamic light scattering. Two-point-probe DC measurements and adhesive force tests are used to determine the conductivity and evaluate adhesion for the positive electrode. Cyclic voltammetry, electrochemical impedance spectroscopy (EIS), and charge/discharge tests are used to analyze the electrochemical properties of the battery. The samples containing 88% LFP, 5.5% Super P, and 6.5% PVDF perform best, with discharge capacities reaching 169.8 mAh g−1 at 0.1 C, and they can also manage charging/discharging of 5 C. EIS indicates that this combination produces the lowest charge-transfer impedance (67 Ω) and the highest Li+ ion diffusion coefficient (5.76 × 10−14 cm2 s−1).

The initial stages of Li2O2 formation during oxygen reduction reaction in Li-O2 batteries: The significance of Li2O2 in charge-transfer reactions within devices

Lithium-oxygen batteries are a promising technology because they can greatly surpass the energy density of lithium-ion batteries. However, this theoretical characteristic has not yet been converted into a real device with high cyclability. Problems with air contamination, metallic lithium reactivity, and complex discharge and charge reactions are the main issues for this technology. A fast and reversible oxygen reduction reaction (ORR) is crucial for good performance of secondary batteries’, but the partial knowledge of its mechanisms, especially when devices are concerned, hinders further development. From this perspective, the present work uses operando Raman experiments and electrochemical impedance spectroscopy (EIS) to assess the first stages of the discharge processes in porous carbon electrodes, following their changes cycle by cycle at initial operation. A growth kinetic formation of the discharge product signal (Li2O2) was observed with operando Raman, indicating a first-order reaction and enabling an analysis by a microkinetic model. The solution mechanism in the evaluated system was ascribed for an equivalent circuit with three time constants. While the time constant for the anode interface reveals to remain relatively constant after the first discharge, its surface seemed to be more non-uniform. The model indicated that the reaction occurs at the Li2O2 surface, decreasing the associated resistance during the initial discharge phase. Furthermore, the growth of Li2O2 forms a hetero-phase between Li2O2/electrolyte, while creating a more compact and homogeneous on the Li2O2/cathode surface. The methodology here described thus offers a way of directly probing changes in surface chemistry evolution during cycling from a device through EIS analysis.

Simple construction of multistage stable silicon-graphite nanosheets composites for lithium-ion batteries

Silicon/carbon composites are considered as the preferred anode materials for high energy density lithium-ion batteries due to their high capacity. However, the high cost of raw materials and the complex preparation process have resulted in expensive cost and poor batch stability of silicon-carbon materials, which have impeded their widespread adoption on a large scale. In this study, a multistage stable silicon-graphite nanosheets composite (Si-NSs/G-NSs@C) with intercalated and core-shell structure was produced from low-cost precursors of silicon nanosheets (Si-NSs) and graphite nanosheets (G-NSs) by simple modification-grafting-coating and heat treatment processes. Benefiting from the effective bonding, citric acid carbon coating, intercalation and core-shell structure, the Si-NSs/G-NSs@C composite exhibits excellent performance for lithium storage. The Si-NSs/G-NSs@C electrode, using the sodium alginate binder system, displays the reversible specific capacity of 821.4 mAh g−1 at 400 mA g−1, with the capacity retention rate of 80% after 200 cycles. When employing lithium polyacrylate as the binder, the composite electrode demonstrates the reversible specific capacities of 1048.9 mAh g−1 at 400 mA g−1 and 723.6 mAh g−1 at 1000 mA g−1. After 200 cycles, the capacity retention rates were 81% and 85%, respectively. In summary, the low-cost precursors, simple and controllable preparation process and excellent electrochemical performance will further promote the market application of silicon/carbon anode materials.

Critical Contribution of Imbalanced Charge Loss to Performance Deterioration of Si-Based Lithium-Ion Cells during Calendar Aging.

Increasing the energy density of lithium-ion batteries, and thereby reducing costs, is a major target for industry and academic research. One of the best opportunities is to replace the traditional graphite anode with a high-capacity anode material, such as silicon. However, Si-based lithium-ion batteries have been widely reported to suffer from a limited calendar life for automobile applications. Heretofore, there lacks a fundamental understanding of calendar aging for rationally developing mitigation strategies. Both open-circuit voltage and voltage-hold aging protocols were utilized to characterize the aging behavior of Si-based cells. Particularly, a high-precision leakage current measurement was applied to quantitatively measure the rate of parasitic reactions at the electrode/electrolyte interface. The rate of parasitic reactions at the Si anode was found 5 times and 15 times faster than those of LiNi0.8Mn0.1Co0.1O2 and LiFePO4 cathodes, respectively. The imbalanced charge loss from parasitic reactions plays a critical role in exacerbating performance deterioration. In addition, a linear relationship between capacity loss and charge consumption from parasitic reactions provides fundamental support to assess calendar life through voltage-hold tests. These new findings imply that longer calendar life can be achieved by suppressing parasitic reactions at the Si anode to balance charge consumption during calendar aging.