NOVELTY - A mechanically improved rechargeable battery comprises: (i) a battery case comprising a positive and a negative electrode terminal; (ii) positive electrode(s) electrically connected to the positive electrode terminal; (iii) negative electrode(s) electrically connected to the negative electrode terminal; (iv) separator(s) between the positive and negative electrodes; and (v) battery electrolyte in the case.    USE - Useful in a variety of industrial and commercial applications, i.e. fork lifts, golf carts, uninterruptible power supplies and electric vehicles.    ADVANTAGE - The rechargeable battery has mechanically and thermally improved battery design, battery module design, and battery pack design.    DETAILED DESCRIPTION - A mechanically improved rechargeable battery comprises:    (a) a battery case comprising a positive and a negative electrode terminal (7, 8);    (b) positive electrode(s), in the case, electrically connected to the positive electrode terminal;    (c) negative electrode(s), in the case, electrically connected to the negative electrode terminal;    (d) separator(s) between the positive and negative electrodes (4, 5); and    (e) battery electrolyte in the case.    The separator electrically insulates the positive electrode from the negative electrode, while allowing for chemical interaction between the positive and negative electrodes. The battery electrolyte surrounds and wets the positive electrode, the negative electrode and the separator. The battery case is prismatic in shape and has an optimized thickness to width to height aspect ratio.    An INDEPENDENT CLAIM is included for a rechargeable battery system formed from at least one interconnected rechargeable battery, exposed to ambient thermal condition, so as to develop a degradative thermal operating temperature in the rechargeable system, comprising a mechanism for providing variable thermal insulation to at least that portion of the rechargeable battery system which is most directly exposed to the ambient thermal condition, so as to maintain the temperature of the rechargeable battery system within the desired operating range under variable ambient conditions.    DESCRIPTION OF DRAWING(S) - The figure shows a stylized depiction of an exploded, cross-sectional view of the mechanically improved rechargeable battery, specifically illustrating how many of the battery components interact when assembled.    Positive and negative electrodes (4, 5)    Positive and a negative electrode terminal (7, 8)