The review also highlights the two most promising future research directions in the field of battery safety: (1) aqueous batteries with expanded electrochemical window of stability, (2) all solid state batteries with low interfacial impedances.
The lithium-ion batteries in modern electric vehicles and electronic gadgets typically use a liquid or gel electrolyte that is highly flammable. An important aim of battery research is to replace such electrolytes with solid materials, which would be safer and could reduce the battery’s weight.
Many industrials, but also some scientists that have a consulting activity, consider that the intrinsic safety of the battery is not so important, since the battery monitoring system (BMS) can be so efficient that it is able to prevent any problem. Recent battery fires show that this view is too optimistic.
A string of recent battery fires has sparked conversations on the safety of Li-ion batteries. A possible path to battery safety is a solid-state battery that replaces the volatile and flammable liquid electrolyte with a nonflammable solid electrolyte. The safety benefits of this solid electrolyte replacement are widely agreed upon.
However, their safety has not been quantitatively evaluated. Here, we initiate a discussion of solid-state battery safety by presenting a thermodynamic investigation of heat release under several failure scenarios with direct comparison with conventional Li-ion batteries.
At normal temperature, a more-uniform temperature distribution among the battery pack is desirable, whereas at high temperatures, good heat insulation between neighboring cells is required. The safety design at the pack level is comprehensive.