Mainly expend. Most of them, after release lives for minutes up to half an hour or so. Often they aren't even charged to full capacity.
Interesting, do you have more information on state of the art non-rechargeable batteries? I would assume they just use normal LiPo cells anyway and just charge them once, ideally at the factory. Cheap, light (compared to the warhead at least), can deliver enough current.
Also they use li-ion cells which can be run to a lower voltage than a lipo, which is normally what the flight controllers are configured for out of the box.