The link goes to a 'cadmium cell', there is no mentioning in the description or visible in the pictures that it would be a saturated one. There are no instructions visible in the picture that it needs to be kept upright, so I think it's a fair assumption that it is indeed an unsaturated one (which seem to be more common).
I trust there C. Hoffman's judgement and think those are chiefly of interest for the steam punk crowd (or the subset thereof which doesn't mind toxic materials around the house), rather than the voltnuts.