Battery with compression and prevention of thermal runaway propagation features

A battery, comprising:

• a metal can having a bottom, a top opening, and four sides;
• and
• a plurality of cells stacked inside the metal can, wherein:
• at least two opposing sides of the four sides of the metal can are biased inward against the plurality of cells to provide compression;
• the plurality of cells are stacked with a plurality of insulation layers and a plurality of double-sided fins;
• a double-sided fin of the plurality of double-sided fins is located between a cell of the plurality of cells and an insulation layer of the plurality of insulation layers;
• intumescent paint is applied to one side of the double-sided fin, the one side facing the insulation layer;
• and
• the intumescent paint is not applied to another side of the double-sided fin facing the cell.