Phone manufacturers typically optimize around a 1 day use case. The battery takes up a significant amount of space and adding more than a day of charge at the expense of a thicker or larger phone typically doesn&#x27;t play out well in the market.<p>A perfect example is the correlation between screen sizes and the launch of LTE. At the time if you asked anyone they wouldn&#x27;t have wanted a larger phone however carriers wanted LTE phones and the market wanted phones that lasted all day. At the time thickness was a fairly standard comparison so what happened? They sold you a bigger screen so that they could fit a larger battery without producing a thicker phone.