High-power Lithium-ion Batteries Research Articles

Tissue paper-based composite separator using nano-SiO2 hybrid crosslinked polymer electrolyte as coating layer for lithium ion battery with superior security and cycle stability

In order to develop high power lithium ion batteries (LIBs), urgent requirements including adequate safety, higher current density and superior cyclic stability are proposed for separator. Tissue paper, composed of packed cellulose fibers, possesses lower production cost, easier accessibility, superior wettability together with outstanding thermostability, and is thus a candidate to be the substrate for high performance separator. To address the issue of structural failure usually encountered by single polymer as binder during long term cycling, crosslinked binder was constructed on tissue paper to adhere nano-SiO2 through chemical reactions between poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) and hyperbranched polyethyleneimine (PEI) in this work. The effects of crosslinking degree on physical properties and electrochemical performance were studied thoroughly. When the feed ratio of PVDF-HFP and PEI is fixed at 10:1, the crosslinked composite separator displays excellent electrolyte uptake and wettability, superior ionic conductivity, better interfacial compatibility as well as higher Li+ transference number (0.56), thus offering battery with prominent rate capabilities. Besides, this crosslinked composite separator exhibits satisfying dimensional stability even treated at 250 °C, better flame retardancy, enhanced mechanical behavior, wider electrochemical window and outstanding cycle stability. Accordingly, tissue paper-based crosslinked composite separators can meet higher requirements put forward by high power LIBs.

The effect of dual-doping on the electrochemical performance of LiNi0.5Mn1.5O4 and its application in full‐cell lithium‐ion batteries

Dual improvement on electrochemical kinetics and lifespan of LiNi0.5Mn1.5O4 (LNMO) cathode material is of great significance for realizing high-power and durable lithium-ion batteries (LIBs). To achieve this goal, the Mg2+−Cr3+ co-doping LNMO microspheres were prepared via the coprecipitation route. FTIR, Raman spectra and magnetic susceptibility verify that both the Mg2+ and Cr3+ doping are beneficial for the formation of disordered Fd3m phase leading to the improvement of electronic conductivity and decrease in electrochemical polarization and the charge transfer resistance (Rct). Meanwhile, the doping also reduces the content of Mn3+ in LNMO which can diminish the dissolution of Mn3+ resulting in the enhancement of cycling life. As a result, the Mg2+−Cr3+ co-doping sample (MC-LNMO) exhibits an improved electrochemical performance (EP). A discharge capacity (DC) of 110.7 mAh/g at 10C can be obtained for MC-LNMO which is higher than that of pure LNMO (only 53 mAh/g) and after 200 cycles the capacity fade is only 4.6% at 25 °C. To further evaluate the MC-LNMO electrode for practical application, in this study, the full cells were also fabricated using the MC-LNMO as cathode and Li4Ti5O12 (LTO) as anode. In the combination, the full device exhibits high energy density (ED) and long cycle life due to the large difference in the working potential of LNMO (4.7 V) and LTO (1.55 V) and their excellent lifespan. These findings provide a simple and scalable method to boost the EP of LNMO, which can be used to fabricate high-quality LIBs.

TiO2 encrusted MXene as a High-Performance anode material for Li-ion batteries

TiO2 has the potential to be a viable anode material for high-power lithium-ion batteries (LIBs). However, the lower electronic conductivity of TiO2 limits its practical applications. Here, the synthesis of novel TiO2 decorated Ti3C-MXene anode for LIBs using in-situ hydrolysis is discussed. MXenes are well known for their outstanding structural stability and superior electronic conductivities; thus, using MXenes as a host material for TiO2 may improve its structural and electrical characteristics. Scanning and transmission electron microscopy (SEM & TEM) examination revealed that the in-situ method resulted in a uniform and comformal coating of TiO2 (27.5 nm) on the inner and outer surfaces of MXene surfaces. BET analysis revealed that the larger surface area of MXene-TiO2 nanocomposite enhanced the active sites for lithium intercalation, which improved electrochemical performance. Furthermore, electrochemical impedance spectroscopy (EIS) analysis revealed faster kinetics for MXene-TiO2 materials when compared to the TiO2 anode. Compared to pristine TiO2 anode, 5 wt% MXene-TiO2 nanocomposite showed significantly better electrochemical performance, with an electrochemical capacity of around 200 mAhg−1 at 0.1C. Nanocomposites based on MXene-TiO2 exhibit outstanding electrochemical performance, indicating the potential for using MXene-based nanocomposites as an anode in high-performance lithium-ion batteries.

Polyimide-derived carbon nanofiber membranes as free-standing anodes for lithium-ion batteries.

Free-standing and flexible carbon nanofiber membranes (CNMs) with a three-dimensional network structure were fabricated based on PMDA/ODA polyimide by combining electrospinning, imidization, and carbonization strategies. The influence of carbonization temperature on the physical-chemical characteristics of CNMs was investigated in detail. The electrochemical performances of CNMs as free-standing electrodes without any binder or conducting materials for lithium-ion batteries were also discussed. Furthermore, the surface state and internal carbon structure had an important effect on the nitrogen state, electrical conductivity, and wettability of CNMs, and then further affected the electrochemical performances. The CNMs/Li metal half-cells exhibited a satisfying charge–discharge cycle performance and excellent rate performance. They showed that the reversible specific capacity of CNMs carbonized at 700 °C could reach as high as 430 mA h g−1 at 50 mA g−1, and the value of the specific capacity remained at 206 mA h g−1 after 500 cycles at a high current density of 1 A g−1. Overall, the newly developed carbon nanofiber membranes will be a promising candidate for flexible electrodes used in high-power lithium-ion batteries, supercapacitors and sodium-ion batteries.

In Situ Self-Catalyzed Formation of Carbon Nanotube Wrapped and Amorphous Nanocarbon Shell Coated Lifepo4 Microclew for High-Power Lithium Ion Batteries

In Situ Self-Catalyzed Formation of Carbon Nanotube Wrapped and Amorphous Nanocarbon Shell Coated Lifepo4 Microclew for High-Power Lithium Ion Batteries

In Situ Self-Catalyzed Formation of Carbon Nanotube Wrapped and Amorphous Nanocarbon Shell Coated Lifepo4 Microclew for High-Power Lithium Ion Batteries

In Situ Self-Catalyzed Formation of Carbon Nanotube Wrapped and Amorphous Nanocarbon Shell Coated Lifepo4 Microclew for High-Power Lithium Ion Batteries

A niobium oxide with a shear structure and planar defects for high-power lithium ion batteries

The micrometer-sized H-Nb2O5 could achieve fast lithium-ion storage by engineering its planar defects.

Improved High-Potential Property of Ni-Rich LiNi0.8Co0.1Mn0.1O2 with a Garnet Ceramic LLZTO Surface Modification in Li-Ion Batteries

The Ni-rich LiNixCoyMn1–x–yO2 with high specific capacity and superior thermal stability under a high cutoff voltage (>4.3 V) will play a critical role in high-power lithium-ion batteries (LIBs). In this paper, LiNi0.8Co0.1Mn0.1O2 (NCM811) equipped with a stable garnet ceramic Li6.5La3Zr1.5Ta0.5O12 (LLZTO) nanoshell is successfully synthesized via a simple wet chemical approach. X-ray diffraction, scanning electron microscope (SEM), energy-dispersive spectrometer (EDS) element mapping, and transmission electron microscopy (TEM) confirm the presence of LLZTO on the NCM811 surface. The NCM811 with 2 wt % LLZTO (2-NCM811) can deliver a superior specific capacity of 144.4 mAh·g–1 at 1C (2.8–4.3 V) after 100 cycles, accompanied by a capacity retention rate as high as 81.1%. But pristine NCM811 has a discharge capacity of only 119.6 mAh·g–1 and a capacity retention rate as low as 69.5% under the same condition. What is more, 2-NCM811 exhibits an enhanced discharge capacity of 129.6 mAh·g–1 at 1C (2.8–4.5 V) after 100 cycles and a high capacity retention rate of 62.9%, which are superior to those of pristine NCM811 (110.0 mAh·g–1, 57.6%). The improved high-potential performance of 2-NCM811 can be attributed to the positive role of the LLZTO shell, which enhances the structural stability and simultaneously inhibits adverse side reactions at the surface of 2-NCM811 during cycling. Based on the above advantages, LLZTO with three-dimensional (3D) diffusion pathways and high ion conductivity is expected to be the most prospective material for the surface modification engineering of nickel-rich cathode materials in lithium-ion batteries (LIBs).

Co3O4-based fluffy tubes structure used as anode material for lithium-ion battery

Herein, a distinctive structure is synthesized by combining multi-walled nanotubes (MWCNTs) with Co3O4. Zif-67 grew densely on MWCNTs and formed a sugar-gourd structure. Then, it carbonized in Ar/H2, and finally oxidized in air to form fluffy tubes. The surface produces a large number of secondary carbon nanotubes, forming conductive tentacles that increase the material's conductivity. Our results show that the material has high cyclical stability. After 100 cycles at the current density of 500 mA g−1, there is still a specific discharge capacity of 714 mAh g−1, and the capacity retention rate is as high as 92.4%. It is a potential anode candidate material for the next generation of high-power Lithium ion batteries (LIBs).

A novel strategy for synthesizing the large size Co9S8@C nanosheets as anode for lithium-ion batteries with superior performance

The cobalt sulfides have become the focus materials on the lithium ion batteries application in which the Co9S8 with the nanosheet structure is the promising candidate for anode material in high-energy and high-power lithium ion batteries. By introducing a novel strategy with the organic-inorganic hybrid Co9S8-DETA (DETA=Diethylenetriamine) as the precursor, the large size Co9S8@C nanosheets have been successfully prepared via a calcination process. Due to uniform two-dimensional structure of Co9S8 and the amorphous carbon layer coating, the as-prepared Co9S8@C nanosheets exhibited excellent lithium ion storage performance as an anode material. The reversible capacity could be retained at 595 mAh g−1 after 160 cycles at 0.2 A g−1. The excellent performances of this nanocomposite offer numerous opportunities for other sulfides as a new anode in lithium ion batteries.

Recent advances of overcharge investigation of lithium-ion batteries

Lithium-ion batteries have been widely used in the power-driven system and energy storage system, while overcharge safety for high-capacity and high-power lithium-ion batteries has been constantly concerned all over the world due to the thermal runaway problems by overcharge occurred in recent years. Therefore, it is very important to study the thermal runaway mechanism and improve the safety of the battery during overcharge. In this work, depending on the external appearance, voltage, and temperature changes, the whole overcharge to TR process was divided into 5 stages. By analyzing the side reactions in five stages, the mechanism of heat production during overcharge is summarized, and the order of heat generation is QCa+An > Qanode > Qelectrolyte > Qcathode > QSEI > QISC. Key factors for battery overcharge safety, such as cathode materials, electrolyte safety, and charging current are concluded in this review. Compared to external protection devices (such as BMS, OSD, CID), the internal protection of overcharge additives are more effective. A complex polymer with aromatic functional groups, epoxy or propionate, will become a hot spot in the research of overcharge additives for lithium-ion batteries. This review is expected to offer effective overcharge safety strategies and promote the development of lithium-ion battery with high-energy density.

Li+ Dynamics of Liquid Electrolytes Nanoconfined in Metal-Organic Frameworks.

Metal–organic frameworks (MOFs) are excellent platforms to design hybrid electrolytes for Li batteries with liquid-like transport and stability against lithium dendrites. We report on Li+ dynamics in quasi-solid electrolytes consisting in Mg-MOF-74 soaked with LiClO4–propylene carbonate (PC) and LiClO4–ethylene carbonate (EC)/dimethyl carbonate (DMC) solutions by combining studies of ion conductivity, nuclear magnetic resonance (NMR) characterization, and spin relaxometry. We investigate nanoconfinement of liquid inside MOFs to characterize the adsorption/solvation mechanism at the basis of Li+ migration in these materials. NMR supports that the liquid is nanoconfined in framework micropores, strongly interacting with their walls and that the nature of the solvent affects Li+ migration in MOFs. Contrary to the “free’’ liquid electrolytes, faster ion dynamics and higher Li+ mobility take place in LiClO4–PC electrolytes when nanoconfined in MOFs demonstrating superionic conductor behavior (conductivity σrt > 0.1 mS cm–1, transport number tLi+ > 0.7). Such properties, including a more stable Li electrodeposition, make MOF-hybrid electrolytes promising for high-power and safer lithium-ion batteries.

Phase change material based passive battery thermal management system to predict delay effect

In the modern scenario of the automobile industry there is a translation from conventional fuel vehicles to electric vehicles as a set to reduce carbon percentage. High power Lithium-ion batteries are the main power source of this vehicle to drive the powertrain, but due to the natural influence of various hot environmental conditions, there is a significant reduction in mileage of vehicle which is not desirable because a lithium-ion battery pack covers 50 to 60% whole cost of vehicle. To tackle this problem from recent years there are several types of research have been performed over active and passive thermal management techniques in which passive thermal management system is widely growth from recent years due to its numerous working advantages with the low-cost application. In the present study, we performed PCM based passive thermal management study over 60 Cell 18,650 Lithium-ion battery packs which are considered to be working for automobile applications. The high-power energy density battery is submerged with a layer of PCM to investigate the delay effect caused by the battery pack to resists the set limit of the threshold temperature range. The output field results from numerical investigation are predicted using neural network approach in which a multi-objective optimization strategy is proposed between battery pack delay effect for selected paraffin wax and RT-18 PCM against its given C-rate. furthermore, liquid fraction rate is monitored for the fixed temperature limit in varying C-rate condition, for optimization strategy Fixed temperature is taken as a function for time delay by PCM addition with liquid fraction rate of PCM over the varying C-rate condition. Correlations suggest paraffin wax is the best choice for a set temperature limit below 60 °C because paraffin wax is found to be melted faster and acts as a resistance to increase the temperature of the cell. The best fit line from the linear regression model using neural network approach suggest best fit line as the time delay is the function of liquid fraction rate over the selected PCM configuration. The highest time delay is occurred in case of paraffin wax PCM as 11,900 s for 1C rate and lowest time delay is occurred as 10,000 s for 1C rate in case of RT-18.

Engineering the architecture and oxygen deficiency of T-Nb2O5-carbon-graphene composite for high-rate lithium-ion batteries

Developing advanced architectures using a cost-effective synthesis strategy is still a challenge for wide-spread commercial application of Nb 2 O 5 in high-power rechargeable lithium-ion batteries (LIBs). Here we report a new two-dimensional (2D) architecture composed of oxygen-vacancy-rich T -Nb 2 O 5 on reduced graphene oxide nanosheet and carbon (2D Nb 2 O 5 -C-rGO), which is synthesized via a one-pot hydrolysis route followed by a heat-treatment. As an anode for LIBs, the 2D Nb 2 O 5 -C-rGO architecture shows excellent rate capability (achieving a capacity of 114 mAh g −1 at 100 C or 20 A g −1 ) and cycling stability (maintaining a capacity of 147 mAh g −1 at 5 C for 1,500 cycles and 107 mAh g −1 at 50 C for 5,000 cycles). Experimental investigations and density functional theory (DFT)-based calculations reveal that the outstanding Li + storage performance of the 2D Nb 2 O 5 -C-rGO electrode is attributed to the enhanced electronic conductivity facilitated by the C-rGO electronic network and fast Li + migration within small Nb 2 O 5 grains enhanced by in-situ formed lattice oxygen vacancies, which alter the Nb d band structure and Li + interaction. This work results in an anode with advanced architecture for fast Li + storage and provides more insight into the energy storage mechanism in the Nb 2 O 5 -based carbonaceous composite electrodes. • A 2D T -Nb 2 O 5 -C-rGO composite anode was synthesized via a cost-effective route. • The architecture and oxygen deficiency were co-engineered by the synthesis route. • High electronic and ionic conductivities were achieved. • The anode delivered a superior rate-capability and stability for Li + storage.

Ultrafine hollow Fe3O4 anode material modified with reduced graphene oxides for high-power lithium-ion batteries

In this work, a composite material consisting of ultrafine Fe3O4 with (ca. 15 nm) uniformly anchored in reduced graphene oxides (rGO) is synthesized and reported to be applied in anodes for lithium-ion battery. The obtained hollow Fe3O4/rGO composites (H-Fe3O4/rGO) (827.3 mA h g−1) has much superior specific capacity than that of the solid Fe3O4/rGO composites (S-Fe3O4/rGO) (654.9 mA h g−1) after 550 cycles of the coin cell at 0.5 A g−1. Even if the cells are tested at 1 A g−1, H-Fe3O4/rGO displays a remarkable specific capacity of 917.4 mA h g−1 as well as the capacity retention rate of 56.7%, compared with S-Fe3O4/rGO (573.9 mA h g−1, the capacity retention rate of 37.7%). Such a sufficient cyclic stability and rate capability in the H-Fe3O4/rGO composite is mainly attributed to the ultrafine hollow structure for shortening Li+ diffusion path and conductive rGO beneficial to rapid electron transfer.

Clarification of particle size dependence on the rate capabilities of Li[Ni1/2Mn3/2]O4 materials and electrodes by the dilute electrode method

Improving the rate capability of lithium insertion electrodes is essential for high-power lithium-ion batteries used in automobile applications. Several approaches have been studied to improve the rate capability of Li[Ni 1/2 Mn 3/2 ]O 4 (LiNiMO); however, no consensus has been reached owing to conflicting results of particle size dependence on rate capability. Rate capability improvement has been obtained previously using nanosized particles as well as micron-sized particles. To solve this contradiction, we examined the dependence of particle size on rate capabilities of LiNiMO materials and electrodes using the dilurted electrode method. This method allows us to measure two distinct rate capabilities of lithium insertion materials and electrodes. The rate capability of dilute-LiNiMO electrodes is improved by using nanosized particles, while that of conventional electrodes is improved by using micron-sized particles. This indicates two different rate-determining steps: Li-ion transport in LiNiMO particles for the dilute electrodes, and Li-ion diffusion in the electrolyte for the conventional LiNiMO electrodes. Moreover, the rate capability of the dilute-LiNiMO electrodes is superior to that of the conventional electrodes, indicating that Li-ion transport in LiNiMO particles is faster than Li-ion diffusion in an electrolyte with porous electrodes. These findings provide important insights for designing electrodes with excellent rate capabilities. • Two types of rate capabilities of Li[Ni 1/2 Mn 3/2 ]O 4 materials and electrodes were measured. • The rate capability of dilute electrodes is improved by using nanosized particles. • The rate capability of conventional electrodes is improved by using micro-sized particles. • The rate capability of the dilute LiNiMO electrodes is superior to that of the conventional electrodes. • Li-ion transport in LiNiMO particles is faster than Li-ion diffusion in an electrolyte with porous electrodes.

A Study to Explore the Suitability of LiNi0.8Co0.15Al0.05O2/Silicon@Graphite Cells for High-Power Lithium-Ion Batteries.

Silicon–graphite (Si@G) anodes are receiving increasing attention because the incorporation of Si enables lithium-ion batteries to reach higher energy density. However, Si suffers from structure rupture due to huge volume changes (ca. 300%). The main challenge for silicon-based anodes is improving their long-term cyclabilities and enabling their charge at fast rates. In this work, we investigate the performance of Si@G composite anode, containing 30 wt.% Si, coupled with a LiNi0.8Co0.15Al0.05O2 (NCA) cathode in a pouch cell configuration. To the best of our knowledge, this is the first report on an NCA/Si@G pouch cell cycled at the 5C rate that delivers specific capacity values of 87 mAh g−1. Several techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and gas chromatography–mass spectrometry (GC–MS) are used to elucidate whether the electrodes and electrolyte suffer irreversible damage when a high C-rate cycling regime is applied, revealing that, in this case, electrode and electrolyte degradation is negligible.

Ionic Liquid-Mediated Mass Transport Channels for Ultrahigh Rate Lithium-Ion Batteries.

Excellent mass transport capability is indispensable to building a high-power lithium-ion battery (LIB) system. Nanomaterials with enhanced electrochemical properties have been used for next-generation high-performance LIBs. However, due to the high surface free energy, nanomaterials tend to form agglomeration. The resulting insufficient mass transport channels limit the high rate performance of nanomaterials. Here, we increase the electrolyte accessibility of nanomaterials through a facile ionic liquid (IL) mediation method. The fluidity and affinity enable the IL to infiltrate into the interstitials of nanomaterial aggregations under capillary force, enhancing the electrochemically active contact area and ensuring rapid mass transport. As a proof of concept, IL-mediated LiFePO4 electrodes delivered extraordinary rate performance (112 and 95 mAh g-1 at 200 and 300 C, respectively). In terms of simplicity, the IL mediation can be used as a general strategy to achieve an ultrahigh rate for LIBs.

A Survey of Wireless Battery Management System: Topology, Emerging Trends, and Challenges

An effective battery management system (BMS) is indispensable for any lithium-ion battery (LIB) powered systems such as electric vehicles (EVs) and stationary grid-tied energy storage systems. Massive wire harness, scalability issue, physical failure of wiring, and high implementation cost and weight are some of the major issues in conventional wired-BMS. One of the promising solutions researchers have come up with is the wireless BMS (WBMS) architecture. Despite research and development on WBMS getting momentum more than a decade ago, it is still in a preliminary stage. Significant further upgradation is required towards developing an industry-ready WBMS, especially for high-power LIB packs. Therefore, an in-depth survey exclusively on WBMS architectures is presented in this article. The aim is to provide a summary of the existing developments as well as to present an informative guide to the research community for future developments by highlighting the issues, emerging trends, and challenges. In-depth analysis of the existing WBMS topologies will not only help the researchers to understand the existing challenges and future research scopes clearly but at the same time enthuse them to focus their research inclination in the domain of WBMS.

Enhanced rate capability of Li4Ti5O12 anode material by a photo-assisted sol–gel route for lithium-ion batteries

Photo-assisted sol–gel route was developed to prepare nanostructured Li4Ti5O12 anode materials. Resulting Li4Ti5O12 powders were characterized by phase analysis, microscopic morphology observation, and cyclic charge/discharge tests. As lithium-ion battery electrode, synthesized Li4Ti5O12 material by using the photo-assisted sol–gel route shows specific capacity of 120 mAh g−1 at 10C discharge rate. Furthermore, this material retains 98% of its initial specific capacity at 0.2C after 50 charge/discharge measurements. Outstanding rate capability and cycling stability of this Li4Ti5O12 material are mainly derived from grain refinement induced by ultraviolet photo-irradiation. Therefore, this photo-assisted sol–gel route is attractive alternative method for preparing electrode materials for high-power lithium-ion battery applications.