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Lithium-ion batteries (LIBs) charging at low temperatures will easily accelerate the aging of LIBs and reduce the useful life. This paper applies advanced multi-factors coupling aging model and bi-objective particle swarm optimization (PSO) algorithm to derive suitable charging patterns for LIBs at low temperatures. Based on the results of orthogonal experiments, which consider the effects of charging rate, charging temperature and charging cut-off voltage on battery aging, the low-temperature capacity degradation model was established. Furthermore, two important yet competing charging objectives, including battery health and charging time, are taken into account simultaneously. These two conflicting charging objectives are traded off by solving a bi-objective optimization problem based on battery electrothermal and aging behavior. Combined with PSO algorithm, the optimal low-temperature charging strategy is obtained. As a result, the three-stage constant current and constant voltage (CC-CV) charging strategy is optimized to balance various combinations of charging objectives. Different tradeoffs are compared and analyzed based on the Pareto frontiers. The verification results show that the optimized three-stage CC-CV charging strategy can effectively offer feasible health-conscious charging with desirable tradeoffs among charging speed and battery health under low-temperature charging conditions. [ABSTRACT FROM AUTHOR]

Irreversible lithium plating, as one of the unwanted side reactions, has a high risk of accelerating degradation to destroy the electrochemical performance of lithium-ion batteries (LIBs). Presently, most of the existing irreversible lithium plating detection methods are qualitative or post-mortem quantitative, and there is still a lack of an effective irreversible lithium plating in-situ quantitative detection method. Here, an in-situ quantitative irreversible lithium plating detection method within the full-lifespan of LIBs is proposed. Multi-battery parallel aging experiments are designed for the two abuse scenarios of low-temperature and high-current. By using scanning electron microscope (SEM), inductively coupled plasma-mass (ICP), and Argon-CP technology, the qualitative evolution and the quantitative detection method of irreversible lithium plating are explored. In order to make the proposed detection method non-destructive, two in-situ factors are analyzed to establish the mapping relationship with the measured irreversible lithium plating. It makes it possible that without post-mortem, the irreversible lithium plating, for the first time, is measured quantitatively only by the in-situ factors extracted from the cycle data. Our work provides a possibility for quantitative and onboard detection of irreversible lithium plating, which is of great significance for the development of battery prognostics and health management (PHM) and echelon utilization. [Display omitted] • The problem of discontinuous aging information caused by post-mortem is solved. • The evolution process of irreversible lithium plating is clearly explored. • The evolution process of SEI film thickness is clearly explored. • In-situ quantitative detection of irreversible lithium plating is proposed. • An online full-lifespan irreversible lithium plating detection framework is built. [ABSTRACT FROM AUTHOR]

The degradation mode is of great significance for reducing the complexity of research on the aging mechanisms of lithium-ion batteries. Previous studies have grouped the aging mechanisms into three degradation modes: conductivity loss (CL), loss of lithium inventory (LLI) and loss of active material (LAM). Combined with electrochemical impedance spectroscopy (EIS), degradation modes can be identified and quantified non-destructively. This paper aims to extend the application of this method to more operating conditions and explore the impact of external factors on the quantitative results. Here, we design a quantification method using two equivalent circuit models to cope with the different trends of impedance spectra during the aging process. Under four conditions, the changing trends of the quantitative values of the three degradation modes are explored and the effects of the state of charge (SoC) and excitation current during EIS measurement are statistically analyzed. It is verified by experiments that LLI and LAM are the most critical aging mechanisms under various conditions. The selection of SoC has a significant effect on the quantitative results, but the influence of the excitation current is not obvious. [ABSTRACT FROM AUTHOR]