Batteries, battery systems, battery submodules, battery operational methods, battery system operational methods, battery charging methods, and battery system charging methods are described. According to one aspect, a battery includes a first battery terminal, a second battery terminal, and a plurality of submodules individually comprising a first submodule terminal, a second submodule terminal, a plurality of rechargeable cells electrically coupled between the first and second submodule-terminals, and switching circuitry configured to electrically couple one of the first and second battery terminals with one of the first and second submodule terminals of one of the submodules during an engaged mode of operation of the one of the submodules and to electrically isolate the one of the first and second battery terminals from the one of the first and second submodule terminals of the one of the submodules during a disengaged mode of operation of the one of the submodules.