Researchers Get a Glimpse Inside Wet-Cells
When you want to study something, ideally you will be able to analyze it in its usual setting, but this is not always possible. Batteries are an example of this as the liquid electrolytes cannot be placed in the equipment normally used to study the devices. Researchers at the Pacific Northwest National Laboratory however have borrowed from life science researchers to make the first measurements of wet-cell batteries.
Within batteries are electrodes and an electrolyte. When charging a battery, negative charges collect on one of the electrodes and positive ions in the electrolyte enter the electrode and bind with the charges. When the battery is discharged, those positive ions return to the electrolyte. Normally researchers observe this process in a dry cell, but wet cells are what occupy our electronics. Fortunately the work at PNNL indicates that what happens in a dry cell is very similar to what happens in a wet cell, with some exceptions. In a dry cell, the ions enter the electrode initially from one end, but in a wet cell the ions penetrate from all sides.
It is definitely important to see that dry-cell observations are still valuable, especially as dry cells are easier to work with. Of course the researchers are going to continue to study wet cells and hopefully find the solid electrolyte interphase layer, which is expected to form on an electrode's surface and impact performance. As it has not been directly observed though, just how it impacts performance is not known.