Redmi 4A comes up with a 3120 Mah battery and the phones battery backup depends upon a number of factors. Follow these steps Go to SECURITY APP - BATTERY USAGE take a look at the number of apps which are consuming a large amount of battery and if there is no use please uninstall it.Below I am attaching the link to the thread which gives you the 20 tips to increase the battery life.

Thank You.