26th Century? Maybe mid-25th? I'm pretty familiar with Trek Tech but somehow "quantum flux" warp drive and torpedoes missed me. I've heard of quantum torpedoes, but not quantum flux (but I missed large swaths of DS9 and Voyager so...maybe.) I'm not sure how I feel about the un-rechargable battery. Seems more wasteful that Starfleet would be into.
They don't actually hold a charge, what they do is extract energy from the quantum fluctuations found in the vacuum of space, over a minute scale there are fluctuation in energy fields, that average to zero energy at a larger scale, if you have a small enough atomic structure, you can actually extract some of this energy and use it to do work. The problem is extracting this energy over time wears out the zero point energy cell that does this work, the atomic structure becomes misaligned and less efficient at extracting vacuum energy, eventually it fails to work at all and needs to be replaced. A new Zero Point Energy cell is manufactured to replace the old one and is modular in design so that it is easily replaced.
Warp Fighters such as this are usually based off of carrier Starships such as the USS Enterprise G.