Fusion cells are a fairly common ammunition and power source within the Empyraeum.

They consist of the typical 'sun in a bottle', vacuum in a magnetic field protected titanium glass tube within an armoured canister. A fusion cell is not a miniature reactor, as such; it contains a self-sustaining reaction but a relatively short term one. Thought a cell can power a suit of reflex or impact armour for weeks and a weapon, at least potentially, for months, it will eventually need more fuel.

Kalshodar backpack reactors can recharge fusion cells by siphoning off some of their considerable resources for trickle charge it. This design feature was implemented in to make sure a Kalshodar far from base would not be left unpowered and vulnerable if he was unable to obtain fresh cells. Soldiers, especially epibatoi, have learned and eventually perfected the trick of 'sparking' exhausted cells back to life with a quick 'fry' of high voltage from the much easier to recharge power cells. Of course, should they apply too much electrical charge...