Apple's next generation 'iPhone 13' may feature increased battery capacity across all models. According to an image shared by leaker L0vetodream, the new models will use one of three batteries...
Presumably, the largest A2653 battery would be used for the Pro Max, the A2656 battery would be for the mid-sized models, and the A2660 would be used for the mini.
You can compare these capacities to Apple's current generation devices at: at 3687mAh for the 12 Pro Max, 2815mAh for the 12/12 Pro, and 2227mAh for the mini.
According to the post, the higher battery capacity may be necessary for the rumored low-temperature polycrystalline oxide (LTPO) thin-film transistor (TFT) OLED panels which feature support for a 120Hz refresh rate