The significance of imperceptible crosstalk in high-energy batteries

High-energy lithium-ion batteries (LIBs) are growing in developing and adoption, but are associated with a rapid capacity fading as well as a high risk of thermal runaway. Apart from the decay of electrode materials, electrolyte and interphases, the imperceptible interaction between electrodes, i.e., crosstalk, is emerging as a critical contributor to the failure of high-energy battery. In this perspective, we pioneer in summarizing and commenting on the imperceptible phenomena. Firstly, the origins of crosstalk are accountable to the release of transition metal ions and singlet oxygen species from the cathode, as well as to the oxidation or reduction of the electrolyte at electrodes. Subsequently, chemical and electrochemical approaches, in-situ spectroscopies and numerical simulations that are accessible for crosstalk detections are outlined. Furthermore, the crosstalk suppression strategies are classified into three aspects including the modification of electrode materials, design of favorable electrolytes, and fabrication of functional separators. Moreover, the essential role of crosstalk in life predictions and safety alerts through machine-learning and artificial intelligence is highlighted. Focusing on electrode crosstalk, this work is expected to be instrumental in enriching the failure theories of high-energy batteries while improving their survivability and predictability.