As per the 3C certifications, the rated capacities of both batteries are 2,845mAh and 2,390mAh. Chinese tipster Digital Chat Station says that the batteries most likely uses Dual-cell technology. Thus, the batteries have a total rated capacity of 4,780mAh and 4,970mAh. The typical or standard value of the battery will be around 5,000mAh.
The tipster further says that the phones support up to 55W of fast charging, which can take about 35 minutes to fully charge the battery. Recent reports suggest that Mi 11 and Mi 11 Pro could arrive with Quad HD+ resolution with a 120Hz high refresh rate. You can check more details about Xiaomi Mi 11 series here. [source]

Alleged Xiaomi Mi 11 and Mi 11 Pro battery appear on 3C certification - 97