After reviewing the above link, I suggest that perhaps in the future, there aren't quite so many different types of batteries anymore, or at least that variety only exist for the civilian world. Perhaps these are, more-so, a military grade universal battery? Additionally I propose the following...
This is a standard issue field quick charge battery (QCB).
To operate, the adaptor switch must be preset to corallate with the voltage of the relevant equipment. To activate, it must then be primed/pumped per the clip handle portion, same concept as late 20th century emergency crank radios. The clip handle must be turned around into a pistol position, and then cocked like a lever action rifle.
This tool only provides a lower quick charge that will provide enough power to last continually for 2 hours. This tool is an inspired evolution from early 21st century emergency solar powered quick chargers for cell phones minus the solar charge component.. Regardless of how many of the primary smartgun batteries a soldier may carry, their power is ultimately spent, so this tool is a great backup for emergency use to avoid being left inoperable in the field after many hours of use.
For those who aren't smartgunners, it's nessesity transends that purpose. These batteries are not just confined to charging the electrical units of their pulse rifles, but rather all electrical equipment within their gear, including the shoulder lamp, nightvision binoculars, laptop for sentry guns, motion trackers, helmet/headgear camera units, or otherwise civilian equipment that may need to be accessed in the field. With so much equipment demanding such power requirements, and the question of how long any given mission may require a soldier to spend out in the field, it becomes that much more apparent the necessity of such a tool. Many soldiers prefer to compensate this factor by carrying multiple tools throughout their webbing to be more assurred about providing a more complete charge for all of their equipment.