Batteries lithium-ion suffer from gradual degradation which is inevitable, even if we know that the fast charge accelerates this process loss of autonomy. This is especially true for batteries NCM, while batteries based on LFP cells are less susceptible to degradation and the negative effects of fast charging. Now a team of researchers has discovered that hydrogen was involved, which had not been mentioned until now.
Batteries wear out even if they are not used, and that is the fault of hydrogen.
A team of researchers from theStanford University discovered that thehydrogen is at the origin of the progressive degradation of lithium-ion batteries. They also found thatthey wear out even when not in use, for exactly the same reason. The team of researchers, led by physicist and chemist Gang Wan, discovered that there are hydrogen protons and electrons that went unnoticed until now and which nevertheless migrate towards the cathode.
Remember that a battery cell consists of two electrodes. The positively charged anode and the negatively charged anode. Between the two electrodes is a separation layer called electrolyte, which allows lithium ions to move between the electrodes. However, this team discovered that this exchange is also accompanied by a hydrogen migration, which is deposited on the cathode and reduces the effectiveness of conduction, gradually eroding the battery capacity.
Preventing its infiltration would extend the life of the batteries
Solid electrolyte batteries currently under development and scheduled to arrive at the end of the decade have already shown reduced tendency to form dendrites and, consequently, less degradation. Dendrite formation is not only responsible for progressive loss autonomy, but also the risk of short circuit when the electrolyte penetrates.
The Stanford University study shed light on the root of a key problem not only for electric cars, but also for a host of consumer electronics devices that also use this type of battery. This hydrogen, they explain, is present in batteries as byproduct of chemical reactions in the electrolyte.
Thanks to these results, the industry now knows that a future avenue for battery development consists of modify the cathode, or to work on theelectrolyte, in order to increase the resistance to hydrogen infiltration. This could lead to less battery degradation, both when using fast charging systems and in all other situations. However, at no time in the research conclusions is it indicated that this discovery will be applied industrially in the short term.