The expanding use of lithium-ion batteries in electric vehicles and other industries has accelerated the need for new efficient charging strategies to enhance the speed and reliability of the charging process without decaying battery performance indices. Numerous attempts have been conducted to establish optimal charging techniques for commercial lithium-ion batteries during the last decade. However, a few of them are devoted to the comprehensive analysis and comparison of the charging techniques from the controloriented perspective for a battery pack. To fill this gap, a review of the most up-to-date charging control methods applied to the lithium-ion battery packs is conducted in this paper. They are broadly classified as non-feedback-based, feedback-based, and intelligent charging methods. Finally, the paper concludes with a comprehensive discussion of the strengths and weaknesses of the reviewed techniques.
INTRODUCTIONRenewable and clean energy sources are necessary to assist in developing sustainable power that supplies plenty of possible innovative technologies, such as electric vehicles (EVs), solar and wind power systems [1,2]. They must reduce our current reliance on some limited sources of energy such as fossil fuel and uranium to alleviate worries about energy, environment, and economy [3]. Consequently, the need for storage has raised up dramatically while rechargeable electrochemical batteries are employed in practically every energy storing device [4].Recent advancements in lithium-ion batteries demonstrate that they exhibit some advantages over other types of rechargeable batteries, including greater power density and higher cell voltages, lower maintenance requirements, longer lifetime, and faster-charging speeds with lower self-discharge rates [5,6]. However, some drawbacks limit the broad adaption of the lithium-ion batteries, associated explicitly with their high cost, short life-cycle, constrained performance temperature, and possible safety infractions caused by overcharge, over-discharge, short circuit, and production defects [5,7]. In addition, a single lithium-ion cell's voltage is limited in the range of 2.4-4.2 V [8], which is not enough for high voltage demand in practical applications; hence, they are usually connected in series as aThis is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.