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This paper aims to solve the parameter identification problem to estimate the parameters in electrochemical models of the lithium-ion battery.

The parameter estimation framework is applied to the Doyle-Fuller-Newman (DFN) model containing a total of 44 parameters. The DFN model is fit to experimental data obtained through the cycling of Li-ion cells. The parameter estimation is performed by minimizing the least-squares difference between the experimentally measured and numerically computed voltage curves. The minimization is performed using a state-of-the-art hybrid minimization algorithm.

The DFN model parameter estimation is performed within 14 h, which is a significant improvement over previous works. The mean absolute error for the converged parameters is less than 7 mV.

To the best of the authors’ knowledge, application of a hybrid optimization framework is new in the field of electrical modelling of lithium-ion cells. This approach saves much time in parameterization of models with a high number of parameters while achieving a high-quality fit.

The need to optimize and simulate lithium-ion cells is of high importance to their durability. It is possible to use semi-empirical models based on equivalent circuits to model the dynamic behavior. Still, parameter identification is a time consuming task if many equivalent circuits are coupled into a finite element-based simulation. The paper aims to discuss these issues.

In this paper the authors present an approach to estimate parameters in a very efficient way by using a single equivalent circuit model as a surrogate model on measurement data. The results of the surrogate model are periodically linked back to the original complex model via the so called space mapping method. The authors validate the approach and compare it to the original problem.

As a remarkable result, the authors report the achieved reduction of computational cost by approximately 87 percent, which equals a speed up factor of 8.

To the best of the authors’ knowledge, using high and low fidelity semi-empirical models combined with space mapping is new in the field of electrical modeling of lithium-ion cells. This approach saves much time in parameterization of coupled models while maintaining high quality results for geometrical and thermal optimization of lithium-ion cells.

THE list given below is based on the selection presented in Dr. Joris Vorstius's Ergebnisse und Fortschritte der Bibliographie in Deutschland seit dem ersten Weltkrieg (Zentralblatt für Bibliothekswesen, Beiheft 74. Leipzig: Harrassowitz 1948, pp.v.172). Up to recently Dr. Vorstius was Director of the Öffentliche Wissenschaftliche Bibliothek in Berlin, the former Prussian State Library, and he has been the editor of the Zentralblatt since 1947. In addition to this survey of bibliographical work done in Germany, he has recently published a study of subject cataloguing in several of the large German learned libraries (Die Sachkatalogisierung in den wisseuschaftlichen Allgemeinbibliotlieken Deutschlands. Leipzig: Harrassowitz 1948, pp.viii.58) and a revised edition of his sketch of library history (Grundzüge der Bibliotheksgeschichte. Vierte, erweiterte Auflage. Leipzig: Harrassowitz 1948, pp.vii.114). In his survey of German bibliography Dr. Vorstius has aimed at making his selection in such a manner as to give a representative cross‐section of the bibliographies devoted to all important fields of scholarship. Works are listed according to their significance irrespective of the form in which they were issued, as monographs, appendixes to books, or contributions to serials. As the book is not likely to come the way of many British librarians, it has been thought useful to give a tabulated survey of bibliographical work done in Germany during the war years covering the period when there was least cultural contact between Germany and England. While thus cutting off a good slice at the beginning of the period covered by Dr. Vorstius's book, I have been able to extend the time range to include the post‐war period. When Dr. Vorstius surveyed the field in 1947, German bibliographical activity had reached a nadir after declining steeply from the second half of the war onwards. For the whole of 1945 Dr. Vorstius lists one single bibliography, devoted to the literature on doves and pigeons. From this trough of the graph, a slightly ascending curve led to the compilation of the first three German post‐war bibliographies, all of them black lists of Nazi literature compiled for purge purposes. That was the only sign of any revival of bibliographic production Dr. Vorstius was able to record. Writing two years later I have been in a position to expand the post‐war component of the list considerably, at least, relatively speaking. Again, in a field where Germany could take a justified pride in her achievement, in the publication of the numerous current bibliographies, Dr. Vorstius's survey of the numerous Zentralblätter and Jahresberichte is a list of war casualties. All these publications had come to an end, most of them long before the end of the war. Dr. Vorstius's book only records the revival of two, the Deutsche National‐bibliographie and the Deutsche Literaturzeitung. Now the list is considerably longer. Considerations of space have prevented me from listing all the extinct current bibliographies with their dates of stoppage under their appropriate headings; I have limited myself to listing those which have been revived or started since the end of the war and those which were started (and in practically all cases came to a speedy end) during the war.