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Li-ion batteries are widely used in industrial applications due to their high energy density, slow material degradation, and low self-discharge. The existing advanced battery management systems (ABMs) in industry employ semiempirical battery models that do not use first-principles understanding to relate battery operation to the relevant physical constraints, which results in conservative battery charging protocols. This article proposes a Quadratic Dynamic Matrix Control (QDMC) approach to minimize the charge time of batteries to reach a desired state of charge (SOC) while taking temperature and voltage constraints into account. This algorithm is based on an input-output model constructed from a first-principles electrochemical battery model known in the literature as the pseudo two-dimensional (P2D) model. In simulations, this approach is shown to significantly reduce charging time. 1 M. Torchio and L. Magni are with the Dipartimento di Ingegneria Civile e Architettura, while D.M. Raimondo is with the Dipartimento di

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All‐solid‐state batteries currently have the disadvantage of low conductivity of the solid electrolytes (SEs) at room temperature and have issues with nonutilized active material (AM) and high reaction overpotentials due to a low SE/AM interface area. These limitations are partially due to the material properties because of the complex, yet nonoptimal production process. Therefore, a model‐based investigation of the influence of microstructural properties on the electronic and ionic conductivities of all‐solid‐state electrodes is conducted. The objective of this work is to highlight the optimization potential of the mixing and premixing of AM, SE, and conducting additive. The results show that the premixing of AM and conducting additives increases the effective electronic conductivity compared with that of the nonpremixed electrodes. It allows a significantly lower additive volume fraction as the percolation threshold of the conducting additive network reaches earlier. Conducting additives are shown to decrease the effective ionic conductivity by increasing the tortuosity of the microstructures, an effect which can be reduced by premixing the conducting additive and SE.

Electrochemical Impedance Spectroscopy measurements and simulations are performed on a nickel manganese cobalt oxide (NMC)/graphite pouch cell. A physico-chemical continuum battery model is extended by a physical ageing model including a Solid Electrolyte Interphase. The model assumes a loss of electrochemically active surface area at anode and cathode as well as a growth of solid electrolyte interphase (SEI) layer thickness. These ageing parameters have been adjusted with an algorithm to achieve agreement between simulated and measured spectra. The results for a 28 mAh pouch cell show that the ageing model is suitable to correlate the change of the impedance spectrum with the degree of degradation of the cell. In detail, SEI thickness is shown to increase by 45 nm, while the anode and cathode loose 20 % and 57 % of their electrochemically active surface area, respectively. In addition, deviating measurement conditions and the end of life of the cell can be indicated by the parameter identification algorithm. Furthermore, it is demonstrated, that the change of the high and low frequency semicircles can be assigned to the anode SEI and cathode respectively.

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Estimation of the State-of-Health (SOH) of Lithium-ion Batteries (LIBs) is commonly conducted using in-situ measurement methods, such as Incremental Capacity Analysis (ICA) and Differential Voltage Analysis (DVA) as well as impedance based techniques. In this study, we present an alternative method for SOH estimation: The nonlinear dynamic measurement method Nonlinear Frequency Response Analysis (NFRA) is shown to be able to estimate capacity fade of LIBs due to loss of active material. Capacity loss correlates with the quotient of the root mean square of the second and the third harmonic response for different excitation amplitudes in the frequency range sensitive to electrochemical reactions at approximately 1 Hz. The results of the experimental cycle-aging study are validated and further analyzed by using a reaction model containing Butler-Volmer kinetics with a dynamic charge balance of the electrode. Simulations show that the NFR quotient and capacity fade due to loss of specific surface area correlate exactly. We identify the NFR quotient as a reliable, easily measurable parameter for the diagnosis of the SOH of LIBs. Therefore, this study reveals a novel approach for SOH estimation of LIBs based on dynamic analysis with NFRA.