Resistance Of Lithium-ion Battery Research Articles

Review of Low-Temperature Performance, Modeling and Heating for Lithium-Ion Batteries

Lithium-ion batteries (LIBs) have the advantages of high energy/power densities, low self-discharge rate, and long cycle life, and thus are widely used in electric vehicles (EVs). However, at low temperatures, the peak power and available energy of LIBs drop sharply, with a high risk of lithium plating during charging. This poor performance significantly impacts the application of EVs in cold weather and dramatically limits the promotion of EVs in high-latitude regions. This challenge recently attracted much attention, especially investigating the performance decrease for LIBs at low temperatures, and exploring the solutions; however, limited reviews exist on this topic. Here, we thoroughly review the state-of-the-arts about battery performance decrease, modeling, and preheating, aiming to drive effective solutions for addressing the low-temperature challenge of LIBs. We outline the performance limitations of LIBs at low temperatures and quantify the significant changes in (dis)charging performance and resistance of LIBs at low temperatures. The various models considering low-temperature influencing factors are also tabulated and summarized, with the modeling improvement for describing low-temperature performance highlighted. Furthermore, we categorize the existing heating methods, and the metrics such as heating rate, energy consumption, and lifetime impact are highlighted to provide fundamental insights into the heating methods. Finally, the limits of current research on low-temperature LIBs are outlined, and an outlook on future research direction is provided.

Characterization of a Practical-Based Ohmic Series Resistance Model under Life-Cycle Changes for a Lithium-Ion Battery

Understanding battery characteristic behaviors is indispensable in designing and managing large-scale battery-based energy storage systems in high-power applications. This paper presents a practical-based characterization method to model the ohmic series resistance of lithium-ion batteries under life-cycle consideration. Aging cells were prepared in a controlled environment, and the testing information was automatically characterized using a developed computer-based battery test system. An experimental methodology based on the cycling of pulse tests is applied for modeling the ohmic series resistance. Several aspects of the testing parameters during the cycling operations, such as the characteristic changes of the ohmic series resistance, amplitudes of the periodic test current, cell capacity, state of charge, and the rate of change of the resistance increment, are also investigated and analyzed so as to fulfill the resistance model. The accuracy of the proposed model is verified by comparing the testing information, showing a satisfactory result.

In-situ EIS to Investigate Influence of Conductive Additive Addition Rate on Charge Transfer Resistance of Lithium Ion Batteries

In order to develop the lithium ion batteries (LIBs) with higher capacity, it is important to select the suitable compositions of conductive additives for the reduction of the internal resistance of the positive and negative electrodes of LIBs1). In the present study, the influence of the conductive additive addition rate on the internal resistance of the positive electrode was investigated by in-situ EIS 2). This method enables us to measure impedance spectra of the positive electrode, negative electrode and cell of LIBs simultaneously without stopping the measurement of charge/discharge curve. The positive electrode was fabricated by screen printing. The mixture of the slurry containing LiCoO2 powder, carbon nanowire (CNW), polyvinylidene fluoride and N-methylpyrrolidone were screen-printed on the aluminum foil. In this case, the compositions of CNW were 8 to 30 wt % as the conductive additive. In order to investigate the effect of CNW on electrochemical properties of LIB, an acetylene black (AB) was used as the conductive additives instead of the CNW. The spherical natural graphite on cupper foil was used as the negative electrode and a lithium wire was used as the reference electrode (RE). All measurements were carried out by the three-electrode cell (Toyo system co. ltd.) at room temperature (25℃) in an argon atmosphere. In the impedance spectrum of the positive electrode measured by the in-situ EIS, three loops were observed on the Nyquist plane. Since the diameter of the loop in the low frequency range was decreased with the increase of the states of charge (SOC), it is considered that this loop is related to the time constant of charge transfer resistance R ct and electric double layer capacitance 2). The values of R ct of the positive electrode estimated from the diameter of the loop in the low frequency range were decreased with increasing with the addition rate of the conductive additive. The effect of the addition rate of the conductive additive of the positive electrode on the values of R ct at each SOC were discussed.

The Mechanism of Decreasing Resistance by SDX™ in Lithium Ion Battery

1. Introduction Practical uses of lithium-ion batteries are rapidly growing especially in large batteries for electric vehicles (EV), energy storage systems (ESS) and so on, but improvements of their characteristics still are strongly demanded. Large improvements of battery characteristics of LFP (LiFePO4) and NMC (LiNi1/3 Mn1/3 Co1/3 O2) as cathode active material, by using ‘SDXTM’ which is a conducting carbon coated aluminum current collector, have been reported [1,2]. The control of internal resistance of lithium ion batteries by the clarification of mechanism of internal resistance is one of the biggest key items to improve them. So the mechanisms of interface resistance between aluminum current collector and cathode active material layer have been investigated and discussed [3]. In the battery which used LFP as cathode active material, recently the quantitative investigation of contribution to electronic resistance reduction of SDXTMand conducting additives was provided by the result of measurement using ELECTRODE RESISTANCE METER (Under development by HIOKI E.E. CORPORATION) which could divide electrode resistance into material resistance and interface resistance (Fig.1). The interface resistance of the cathde with aluminum current collectors was higher than the material resistance of that by almost one order of magnitude. The interface resistance of the cathode with SDXTMwas lower than that with aluminum current collectors by almost one order of magnitude. Because the interface resistance was reduced by SDXTM, it was reported that conducting additives were able to be reduced much in cathode [4]. In this paper, more detailed examination will be carried out, and the effect of SDXTMin lithium ion battery will be tried to be clarified. 2. Experiment The preparation of electrode slurry was carried out by dispersing LFP as cathode active material, conducting additives and polyvinylidene difluoride (PVdF) into N-methylpyrrolidone (NMP). Cathode electrodes were prepared by coating the slurry onto SDXTM or aluminum current collectors in several coating speeds (e.g. 300, 400 or 500mm/min), by drying and by pressing them. Artificial graphite (SCMGTM) was used for anode active material, and similarly anode electrodes were prepared by coating its slurry (aqueous solution) onto copper current collectors, by drying and by pressing them. By laminating one sheet of anode and one sheet of cathode, pouch type cell was assembled. 3. Results and discussion The material resistance and the interface resistance of the cathode were measured by ELECTRODE RESISTANCE METER (Fig.2). In each coating speed, the interface resistance of the cathode with aluminum current collectors was higher than the material resistance of that. The interface resistance of the cathode with SDXTM was lower than that with aluminum current collectors, and it was almost same as the material resistance of the cathode with SDXTM. The interface resistance of the cathode with aluminum current collectors increased when the coating speed increased, but the interface resistance of the cathode with SDXTMwas constant without depending on coating speed. Cell DCRs were measured (Fig.3). The cell DCR with aluminum current collectors increased when the coating speed increased, but the cell DCR with SDXTMwas constant without depending on coating speed. It was confirmed that the cell DCR with aluminum current collector showed similar behavior to the interface resistance of the cathode with aluminum current collector. The visualization results of a dispersion state of conducting additive in an electrode will be presented.

On-line Measurement of Internal Resistance of Lithium Ion Battery for EV and Its Application Research

Internal resistance of the battery can really reflect its own characteristics, which including health status of the battery, inconsistency, state of charge, thermal runaway. On-line measurement of internal resistance can real-time monitor the running state of each battery and accurately, can report fault state of the battery and handle fault in time. This paper implements the practical engineering module of on-line measurement of internal resistance of lithium ion battery for EV (Electric Vehicle) using AC analysis. The detection precision and stability of the module are less than 0.3%. Based on experiments, the paper studies the stability and temperature characteristic of internal resistance of lithium battery. It also studies the relationship between the internal resistance and SOC, charging current with experiments. This paper analyzes the relationship between the internal resistance and default of the battery, such as inconsistency of batteries, excessive charging current, changing of work state, overcharging.

Calculation and Characteristics Analysis of Lithium Ion Batteries’ Internal Resistance Using HPPC Test

Internal resistance of battery can really reflect its own characteristics, which including health status of the battery, inconsistency, state of charge, thermal runaway. Method to calculate the internal resistance of the battery using HPPC (Hybrid Pulse Power Characterization) test which proposed by the FreedomCAR is introduced. Ohmic resistance, polarization resistance, discharge resistance and regen resistance are calculated based on MATLAB programming using HPPC test. The differences between the four kinds of internal resistance of lithium ion batteries are compared. Characteristics of the four kinds of internal resistance in charged-state and discharged-state are analyzed.

Online Measurement of Battery Internal Resistance Based on AC Impedance Method

In this paper, the merit and disadvantage of existing measurement methods for battery internal resistance are firstly analyzed. Then an online internal resistance measurement based on AC impedance method is proposed, which can increase the stability of the excitation source and enhance the performance of the filtered feedback signal. The method can be used to measure the small resistance of lithium-ion battery precisely. Experimental results show that the proposed method is accurate.

Analysis of Adverse Effects on Vehicle Performance Due to Hybrid Vehicle Battery Deterioration

This paper presents the results of analysis into the adverse effects on vehicle performance caused by the deterioration in capacity and increase in resistance of lithium-ion batteries installed in hybrid electric vehicles (HEVs). Detailed evaluations were conducted based on simulations to determine the adverse effects on HEV performance. It was concluded that the battery resistance at which the CO2 emissions rate and the Fuel Consumption reaches 120% of the level of a new vehicle is approximately 350% of the initial battery resistance value.

Nanomaterials for lithium ion batteries

Nanostructured materials are currently of interest for lithium ion storage devices because of their high surface area, porosity, etc. These characteristics make it possible to introduce new active reactions, decrease the path length for Li ion transport, reduce the specific surface current rate, and improve stability and specific capacity. Moreover, composite nanostructured materials designed to include electronic conductive paths could decrease the inner resistance of lithium ion batteries, leading to higher specific capacities even at high charge/discharge current rates.