What is the autonomy of electric bicycles equipped with the Shimano Steps system?

The range of an electric bicycle is one of the most important issues when choosing an e-MTB. While battery capacity is a very important factor to consider, it is also vital to know which of the manufacturer's technologies are working both to improve and control the autonomy of the bicycle and to reserve some energy in case the battery is completely drained. What autonomy does the Shimano Steps electric assistance system have? What technologies does it use?