Abstract: Provided are electrochemical cell assemblies and methods of fabricating thereof. A cell assembly includes an anode containing lithium titanium oxide and a cathode forming a jellyroll together with the anode. Each of the electrodes is connected to a separate cap and electrically insulated from the case. As such, the case is electrochemically neutral and may be made from a larger selection of materials. For example, a case may be made from steel that would otherwise dissolve if exposed to the anode potential during cycling of the battery. Some of these case materials simplify processing and sealing characteristics. In certain embodiments, a case may be crimped around each of the caps and corresponding gaskets to provide sealing interfaces. The caps or at least their surfaces exposed to the electrolyte are made from materials that are electrochemically stable at corresponding potentials of the electrodes.