A battery module includes: a positive electrode member having a positive electrode current collector, a first positive electrode active material layer, and a second positive electrode active material layer; a negative electrode member having a negative electrode current collector, a first negative electrode active material layer, and a second negative electrode active material layer; and a separator. The positive electrode current collector has a positive electrode folded-back portion. The negative electrode current collector has a negative electrode folded-back portion. The first negative electrode active material layer constitutes a first electrode together with the first positive electrode active material layer. The second negative electrode active material layer constitutes a second electrode connected in parallel with the first electrode together with the second positive electrode active material layer.