Battery life depends on the model, screen brightness and how you use the tablet. Streaming, gaming and high brightness use more power than reading or browsing.
For example, the Redmi Pad SE 8.7 has a 6,650mAh battery and is rated for up to 22.1 hours of video playback, while the Xiaomi Pad 7 has an 8,850mAh battery and supports 45W charging.