Each cell of a battery stores electrical energy as chemical energy in two electrodes, a reductant (anode) and an oxidant (cathode), separated by an electrolyte that transfers the ionic component of the chemical reaction inside the cell and forces the electronic component outside the battery. The output on discharge is an external electronic current I at a voltage V for a time Δt. The chemical reaction of a rechargeable battery must be reversible on the application of a charging I and V. Critical parameters of a rechargeable battery are safety, density of energy that can be stored at a specific power input and retrieved at a specific power output, cycle and shelf life, storage efficiency, and cost of fabrication. Conventional ambient-temperature rechargeable batteries have solid electrodes and a liquid electrolyte. The positive electrode (cathode) consists of a host framework into which the mobile (working) cation is inserted reversibly over a finite solid–solution range. The solid–solution range, which is...

The Li-ion rechargeable battery: a perspective.

Lithium (Li) metal is an ideal anode material for rechargeable batteries due to its extremely high theoretical specific capacity (3860 mA h g−1), low density (0.59 g cm−3) and the lowest negative electrochemical potential (−3.040 V vs. the standard hydrogen electrode). Unfortunately, uncontrollable dendritic Li growth and limited Coulombic efficiency during Li deposition/stripping inherent in these batteries have prevented their practical applications over the past 40 years. With the emergence of post-Li-ion batteries, safe and efficient operation of Li metal anodes has become an enabling technology which may determine the fate of several promising candidates for the next generation energy storage systems, including rechargeable Li–air batteries, Li–S batteries, and Li metal batteries which utilize intercalation compounds as cathodes. In this paper, various factors that affect the morphology and Coulombic efficiency of Li metal anodes have been analyzed. Technologies utilized to characterize the morphology of Li deposition and the results obtained by modelling of Li dendrite growth have also been reviewed. Finally, recent development and urgent need in this field are discussed.

Lithium metal anodes for rechargeable batteries

Solid-state electrolytes are attracting increasing interest for electrochemical energy storage technologies. In this Review, we provide a background overview and discuss the state of the art, ion-transport mechanisms and fundamental properties of solid-state electrolyte materials of interest for energy storage applications. We focus on recent advances in various classes of battery chemistries and systems that are enabled by solid electrolytes, including all-solid-state lithium-ion batteries and emerging solid-electrolyte lithium batteries that feature cathodes with liquid or gaseous active materials (for example, lithium–air, lithium–sulfur and lithium–bromine systems). A low-cost, safe, aqueous electrochemical energy storage concept with a ‘mediator-ion’ solid electrolyte is also discussed. Advanced battery systems based on solid electrolytes would revitalize the rechargeable battery field because of their safety, excellent stability, long cycle lives and low cost. However, great effort will be needed to implement solid-electrolyte batteries as viable energy storage systems. In this context, we discuss the main issues that must be addressed, such as achieving acceptable ionic conductivity, electrochemical stability and mechanical properties of the solid electrolytes, as well as a compatible electrolyte/electrode interface. This Review details recent advances in battery chemistries and systems enabled by solid electrolytes, including all-solid-state lithium-ion, lithium–air, lithium–sulfur and lithium–bromine batteries, as well as an aqueous battery concept with a mediator-ion solid electrolyte.

Lithium battery chemistries enabled by solid-state electrolytes

The escalating and unpredictable cost of oil, the concentration of major oil resources in the hands of a few politically sensitive nations, and the long-term impact of CO2 emissions on global climate constitute a major challenge for the 21st century. They also constitute a major incentive to harness alternative sources of energy and means of vehicle propulsion. Today's lithium-ion batteries, although suitable for small-scale devices, do not yet have sufficient energy or life for use in vehicles that would match the performance of internal combustion vehicles. Energy densities 2 and 5 times greater are required to meet the performance goals of a future generation of plug-in hybrid-electric vehicles (PHEVs) with a 40–80 mile all-electric range, and all-electric vehicles (EVs) with a 300–400 mile range, respectively. Major advances have been made in lithium-battery technology over the past two decades by the discovery of new materials and designs through intuitive approaches, experimental and predictive reasoning, and meticulous control of surface structures and chemical reactions. Further improvements in energy density of factors of two to three may yet be achievable for current day lithium-ion systems; factors of five or more may be possible for lithium–oxygen systems, ultimately leading to our ability to confine extremely high potential energy in a small volume without compromising safety, but only if daunting technological barriers can be overcome.

Electrical energy storage for transportation—approaching the limits of, and going beyond, lithium-ion batteries

Zinc–air is a century-old battery technology but has attracted revived interest recently. With larger storage capacity at a fraction of the cost compared to lithium-ion, zinc–air batteries clearly represent one of the most viable future options to powering electric vehicles. However, some technical problems associated with them have yet to be resolved. In this review, we present the fundamentals, challenges and latest exciting advances related to zinc–air research. Detailed discussion will be organized around the individual components of the system – from zinc electrodes, electrolytes, and separators to air electrodes and oxygen electrocatalysts in sequential order for both primary and electrically/mechanically rechargeable types. The detrimental effect of CO2 on battery performance is also emphasized, and possible solutions summarized. Finally, other metal–air batteries are briefly overviewed and compared in favor of zinc–air.

/pdf/recent-advances-in-zinc-air-batteries-5fiw4wwwgg.pdf

Recent advances in zinc–air batteries

Lithium/air batteries, based on their high theoretical specific energy, are an extremely attractive technology for electrical energy storage that could make long-range electric vehicles widely affordable. However, the impact of this technology has so far fallen short of its potential due to several daunting challenges. In nonaqueous Li/air cells, reversible chemistry with a high current efficiency over several cycles has not yet been established, and the deposition of an electrically resistive discharge product appears to limit the capacity. Aqueous cells require water-stable lithium-protection membranes that tend to be thick, heavy, and highly resistive. Both types of cell suffer from poor oxygen redox kinetics at the positive electrode and deleterious volume and morphology changes at the negative electrode. Closed Li/air systems that include oxygen storage are much larger and heavier than open systems, but so far oxygen- and OH − -selective membranes are not effective in preventing contamination of cells. In this review we discuss the most critical challenges to developing robust, high-energy Li/air batteries and suggest future research directions to understand and overcome these challenges. We predict that Li/air batteries will primarily remain a research topic for the next several years. However, if the fundamental challenges can be met, the Li/air battery has the potential to significantly surpass the energy storage capability of today’s Li-ion batteries.

https://iopscience.iop.org/article/10.1149/2.086202jes/pdf

A Critical Review of Li/Air Batteries

Die Erfindung betrifft ein Verfahren zum Ermitteln des Ist-Ladezustands eines elektrischen Akkumulators. Das Verfahren umfasst: Erfassen des dem Akkumulator zugefuhrten und dem von dem Akkumulator abfliesenden Akkumulatorstrom; Vorsehen einer Ladungsdifferenz durch Integrieren des Akkumulatorstroms uber die Zeit; Aktualisieren eines Messungs-Ladezustands durch Addieren der Ladungsdifferenz zu dem Messungs-Ladezustand; und Ableiten eines Schatzungs-Ladezustands aus einer eindeutigen, vorgegebenen Zuordnung zwischen Ladezustanden und Leerlaufspannungen des Akkumulators ausgehend von einer Leerlaufspannung des Akkumulators. Ein Gutewert wird vorgesehen, der die Genauigkeit des abgeleiteten Schatzungs-Ladezustands wiedergibt und der Schatzungs-Ladezustand wird gemas einem Schatzungs-Gewichtungsfaktor gewichtet. Hierbei ist der Schatzungs-Gewichtungsfaktor von dem Gutewert gemas einer monoton steigenden Funktion abhangig. Ferner umfasst das Verfahren: Gewichten des Messungs-Ladezustands gemas einem Messungs-Gewichtungsfaktor, wobei der Messungs-Gewichtungsfaktor von dem Gutewert gemas einer monoton fallenden Funktion abhangt; und Addieren des gewichteten Schatzungs-Ladezustands mit dem gewichteten Messungs-Ladezustand, um den Ist-Ladezustand vorzusehen. Die Erfindung betrifft ferner eine Vorrichtung zur Ausfuhrung des Verfahrens.

Verfahren und Vorrichtung zum Ermitteln des Ladezustands eines Akkumulators

In a method for determining the state of charge of an electrical accumulator, individual cell voltages are recorded, and the highest and/or the lowest individual cell voltage is ascertained. A present maximum charge and/or a present minimum charge of the appertaining accumulator cell is determined using a characteristic curve and the highest and/or the lowest individual cell voltage.

State of charge determination for an electrical accumulator

A sensor element for determining a physical property of a test gas, eg, the concentration of a gas component in a gas mixture, in particular the oxygen concentration in the exhaust gas from internal combustion engines, has a solid electrolyte body, an external electrode exposed to the test gas situated on the solid electrolyte body, an internal electrode situated in the solid electrolyte body, and an electrical resistance heater which has a meandering heating surface situated in the solid electrolyte body, and is embedded in insulation The external electrode is situated in a cavity formed in the solid electrolyte body to reduce the heat losses from the sensor element due to convection and radiation to the cold test gas flow

Sensor Element For Determining The Physical Property Of A Test Gas

Die Erfindung betrifft ein Verfahren zur Bestimmung des Ladezustands eines elektrischen Speichers. Ferner betrifft die Erfindung eine entsprechende Erfassungsvorrichtung.

Ralf Liedtke

Papers

A Critical Review of Li/Air Batteries

Verfahren und Vorrichtung zum Ermitteln des Ladezustands eines Akkumulators

State of charge determination for an electrical accumulator

Sensor Element For Determining The Physical Property Of A Test Gas

Ladezustandsbestimmung für einen elektrischen speicher