充电机的现状及其发展

充电机是每个汽修部门必备的最基本设备之一,长期以来,由于其技术含量低、生产容易,致使市场上充满了结构简单、价格低廉、有些甚至连最基本的进出线绝缘隔离也没有的劣质产品.使用这些充电机轻则影响蓄电池的充放电寿命,重则干扰电网正常供电,直接威胁使用者的人身安全,实在有必要引起我们的注意.

基于产业化电动车充电方法的应用研究

文章研究的慢充式下开发长寿命充电模式,可有效延长电池的使用寿命,具有一定的创造性;快充充电方法综合电池温度、电池单体电压两者因素,可较好的兼容充电时长、使用寿命、安全性能,目前在已量产车型上应用成功,实用性很强。

A Design of the Automatic Power-off after the Storage Battery of Electric Bicycle Is Fully Charged

As the service life of the electric bicycle＇ s storage battery is shortened due to the long-term floating charge, an automatic power- off circuit for the storage battery of electric bicycle is designed, and also the composition and design of the circuit are specifically expounded. After a test, the circuit can achieve a desired effect. Therefore, it can prolong the service life of the electric bicycle＇ s storage battery and save electric energy in the actual applications.

Remaining Useful Life Prediction of Li-Po Batteries in UAVs Using Extended Kalman Filter

The use of batteries in UAVs （unmanned aerial vehicles） has become common due to some advantages in comparison with internal combustion engines such as weight reduction and better power control. However, in these vehicles it is critical to monitor the RUL （remaining useful life） of the batteries. This information can be used, for instance, as a decision support tool to define which missions could be assigned to the UAV until the next battery recharge. This work presents a methodology to predict the RUL of Li-Po （Lithium-Polymer） batteries. The approach uses an extended Kalman filter and an exponential model for the degradation evolution. The proposed methodology uses time series of battery terminal voltages, assuming that the discharge occurs under a constant current condition. Different discharge current levels were considered.The results showed that the proposed methodology provides good results, despite its simplicity.

Stabilizing the cycling stability of rechargeable lithium metal batteries with tris(hexafluoroisopropyl)phosphate additive

The application of rechargeable lithium metal batteries(LMBs)has been hindered by the fast growth of lithium dendrites during charge and the limited cycling life because of the decomposition of the electrolyte at the interface.Here,we have developed a non-flammable triethyl phosphate(TEP)-based electrolyte with tris(hexafluoroisopropyl)phosphate(THFP)as an additive.The polar nature of the C–F bonding and the rich CF3 groups in THFP lowers its LUMO energy and HOMO energy to help form a stable,Li F-rich solid electrolyte interphase(SEI)layer through the reduction of THFP and increases the binding ability of the PF6-anions,which significantly suppresses lithium dendrite growth and reduces the electrolyte decomposition.Moreover,THFP participates in the formation of a thin,C–F rich electrolyte interphase(CEI)layer to provide the stable cycling of the cathode at a high voltage.The symmetric Li||Li and full Li/NCM622 cells with THFP additive have small polarization and long cycling life,which demonstrates the importance of the additive to the application of the LMBs.

SnSe2 nanocrystals coupled with hierarchical porous carbon microspheres for long-life sodium ion battery anode

Tin selenides have been attracting great attention as anode materials for the state-of-the-art rechargeable sodium-ion batteries(SIBs)due to their high theoretical capacity and low cost.However,they deliver unsatisfactory performance in practice,owing to their intrinsically low conductivity,sluggish kinetics and volume expansion during the charge-discharge process.Herein,we demonstrate the synthesis of SnSe2 nanocrystals coupled with hierarchical porous carbon(SnSe2 NCs/C)microspheres for boosting SIBs in terms of capacity,rate ability and durability.The unique structure of SnSe2 NCs/C possesses several advantages,including inhibiting the agglomeration of SnSe2 nanoparticles,relieving the volume expansion,accelerating the diffusion kinetics of electrons/ions,enhancing the contact area between the electrode and electrolyte and improving the structural stability of the composite.As a result,the as-obtained SnSe2 NCs/C microspheres show a high reversible capacity(565 mA h g^-1 after 100 cycles at 100 mA g^-1),excellent rate capability,and long cycling life stability(363 mA h g^-1 at1 A g^-1 after 1000 cycles),which represent the best performances among the reported SIBs based on SnSe2-based anode materials.

Confining ultrafine SnS nanoparticles in hollow multichannel carbon nanofibers for boosting potassium storage properties

SnS has been extensively investigated as a potential anode material in potassium-ion batteries (PIBs) for its high theoretical capacity.Nonetheless,it suffers a limited cyclic lifespan owing to its poor electronic conductivity and huge volume expansion.This work proposed a facile approach where SnS nanocrystals are confined in the walls of hollow multichannel carbon nanofibers (denoted SnS@HMCFs) to tackle the issues above.In contrast to previous studies,impregnated ultrafine SnS nanocrystals in HMCFs compactly can increase the SnS loading number per unit area of the carbon matrix.Furthermore,the unique hollow multichannel carbon nanofibers are used as a robust carrier to uniformly distribute the SnS nanocrystals.This can significantly accelerate K;/electron transport,resulting in large specific capacity,outstanding rate performance,and steady cycling property for PIBs.High reversible capacities of 415.5 mAh g^(-1)at0.1 A g^(-1)after 300 cycles and 245.5 mAh g^(-1)at 1 A g^(-1)after 1000 cycles are retained,suggesting great potential of SnS@HMCFs as a negative electrode material for PIBs.Additionally,when the SnS@HMCF anode is assembled with the KVPO_(4)F cathode,the obtained full cell shows a large discharge capacity of165.3 m Ah g^(-1)after 200 cycles at 0.1 A g^(-1).

Carbon-coated Fe2O3 hollow sea urchin nanostructures as high-performance anode materials for lithium-ion battery

Fe2O3 has become a promising anode material in lithium-ion batteries (LIBs) in light of its low cost, high theoretical capacity (1007 mA h g^−1) and abundant reserves on the earth. Nevertheless, the practical application of Fe2O3 as the anode material in LIBs is greatly hindered by several severe issues, such as drastic capacity falloff, short cyclic life and huge volume change during the charge/discharge process. To tackle these limitations, carbon-coated Fe2O3 (Fe2O3@MOFC) composites with a hollow sea urchin nanostructure were prepared by an effective and controllable morphology-inherited strategy. Metal-organic framework (MOF)-coated FeOOH (FeOOH@-MIL-100(Fe)) was applied as the precursor and self-sacrificial template. During annealing, the outer MOF layer protected the structure of inner Fe2O3 from collapsing and converted to a carbon coating layer in situ. When applied as anode materials in LIBs, Fe2O3@MOFC composites showed an initial discharge capacity of 1366.9 mA h g^−1 and a capacity preservation of 1551.3 mA h g^−1 after 200 cycles at a current density of 0.1 A g^−1. When increasing the current density to 1 A g^−1, a reversible and high capacity of 1208.6 mA h g^−1 was obtained. The enhanced electrochemical performance was attributed to the MOF-derived carbon coating layers and the unique hollow sea urchin nanostructures. They mitigated the effects of volume expansion, increased the lithium-ion mobility of electrode, and stabilized the as-formed solid electrolyte interphase films.

1,3-Dimethyl-2-imidazolidinone: an ideal electrolyte solvent for high-performance Li–O;battery with pretreated Li anode

Electrolytes are widely considered as a key component in Li–O;batteries (LOBs) because they greatly affect the discharge-charge reaction kinetics and reversibility.Herein,we report that 1,3-dimethyl-2-imidazolidinone (DMI) is an excellent electrolyte solvent for LOBs.Comparing with conventional ether and sulfone based electrolytes,it has higher Li_(2)O_(2)and Li_(2)CO_(3)solubility,which on the one hand depresses cathode passivation during discharge,and on the other hand promotes the liquid-phase redox shuttling during charge,and consequently lowers the overpotential and improves the cyclability of the battery.However,despite the many advantages at the cathode side,DMI is not stable with bare Li anode.Thus,we have developed a pretreatment method to grow a protective artificial solid-state electrolyte interface(SEI) to prevent the unfavorable side-reactions on Li.The SEI film was formed via the reaction between fluorine-rich organic reagents and Li metal.It is composed of highly Li^(+)-conducting Li_(x)BO_(y),LiF,Li_(x)NO_(y),Li_(3)N particles and some organic compounds,in which Li_(x)BO_(y)serves as a binder to enhance its mechanical strength.With the protective SEI,the coulombic efficiency of Li plating/stripping in DMI electrolyte increased from 20%to 98.5%and the fixed capacity cycle life of the assembled LOB was elongated to205 rounds,which was almost fivefold of the cycle life in dimethyl sulfoxide (DMSO) or tetraglyme(TEGDME) based electrolytes.Our work demonstrates that molecular polarity and ionic solvation structure are the primary issues to be considered when designing high performance Li–O;battery electrolytes,and cross-linked artificial SEI is effective in improving the anodic stability.

The way to improve the energy density of supercapacitors:Progress and perspective

Compared with other energy storage devices, supercapacitors have superior qualities,including a long cycling life,fast charge/discharge processes,and a high safety rating.The practical use of supercapacitor devices is hindered by their low energy density.Here,we briefly review the factors that influence the energy density of supercapacitors.Furthermore,possible pathways for enhancing the energy density via improving capacitance and working voltage are discussed. In particular,we offer our perspective on the most exciting developments regarding high-energy-density supercapacitors, with an emphasis on future trends.We conclude by discussing the various types of supercapacitors and highlight crucial tasks for achieving a high energy density.