Factors Which Limit the Cycle Life of Rechargeable Lithium (Metal) Batteries

Abstract

Failure mechanisms due to high charging rates of rechargeable lithium batteries comprised of Li metal anodes, Li 0.3 MnO 2 cathodes (tunneled structure), and electrolyte solutions based on the combination of 1,3-dioxolane (DN), LiAsF 6 , and tributylamine (antipolymerization stabilizer) were explored with the aid of postmortem analysis. It was found that at high charging rates, lithium deposition produces small grains, which are too reactive toward the electrolyte solution, in spite of the excellent passivation of lithium in this solution. In practical batteries such as AA cells with spirally wound configurations, the amount of solution is relatively small, and the solution is spread throughout the battery in a thin layer. Therefore, upon cycling, the Li-solution reactions deplete the amount of the solution below a critical value, so that only part of the active materials continues to function. This leads to a pronounced increase in the internal resistance of these batteries, which fail as a result of their high impedance and the decrease in the effective working electrodes area. Another failure mechanism relates to the extremely high charge-discharge current densities developed as the active electrode area decreases. These high currents, developed after prolonged cycling, lead to the formation of dendrites that short-circuit the battery, thus terminating its life.

Improving battery safety by early detection of internal shorting with a bifunctional separator

“…In the lithium metal rechargeable battery, lithium dendrites gradually grow on the surface of the lithium metal electrode during each discharge-recharge cycle 7 . These dendrites can penetrate through the polymer separator to form a short circuit between the positive and negative electrodes 9 , which can initiate exothermic reactions between the electrodes and the flammable organic electrolyte 10,11 . The excess of heat released in these reactions often induces fire and even explosions.…”

Manipulating surface reactions in lithium–sulphur batteries using hybrid anode structures

“…For any rechargeable batteries employing Li metal as the anode, two major failure mechanisms are typically associated with the system. One is the uncontrolled dendrite formation 44 , whereas the other is the continuous evolution of a porous, or mossy, Li metal structure that lowers cell efficiency 45 . The former presents serious safety issues, particularly at high charging rates, whereas the latter continually erodes the anode.…”

Stochastic coordinated operation of wind and battery energy storage system considering battery degradation

“…Equations (24)- (26) set power limits for BESS charging/discharging levels, indicating the BESS cannot charge and discharge at the same time. Equations (27) and (28) represent the SoC limits, and the relationship between SoC and the BESS charging/discharging behavior. Note that the SoC at the end of H-1 in S 1 must be the same as the SoC at the beginning of H in S 2 .…”

“…Multiple factors contribute to battery degradation, such as temperature, charging/discharging current rate, SoC, depth of discharge (DoD), and cycling regime. For example, one of the major factors that limits the cycle life for certain lithium-ion batteries (such as Li 0.3 MnO 2 ) is DoD due to reactions with deposited lithium [27]. Cycling the battery at a high DoD can therefore dramatically reduce the number of lifetime cycles for lithium-ion batteries [28].…”