All depends on what current is being applied and the configuration of the battery to accept it because there's the issue of temperature and the risk of damaging the specifications about capacity and available recharging cycles. Some manufacturers of Ni-MH rechargeable batteries write a clear indication on them for warning in accordance to the risks of fast charging. Others don't and even recommend some types of fast chargers. Then? It seems that the battery is not hurt in the process of fast charging […], but it must exist a more elaborated answer.
With Li-ion technology, there's rapid and fast charging with 3h and 1h respectively. According to this theory, in ideal conditions, a battery could be charged to 100% in a mere hour. Electric vehicle batteries are as of today mostly based on this technology, thus this would be possible. Besides, the charging curve is similar to an exponential, taking more charge in the first period.
That's why some of the fastest chargers provide more than 100 miles of range in a 30 minute charging period. This market is now providing highly convenient options as it covers a broad spectrum of needs. For everyday use, with more economic energy and enough range. The best of all is working to have a cleaner atmosphere, and air in general without noxious implications on the habitat in which we live.
Even if some is not still perfect, it would be with a standardization of batteries and a fast swap system. Let's remind other time that 30 minutes of charge and a limited range doesn't guarantee freedom for long distance traveling and all of it would be solved if service stations provide a fast method to swap the batteries. There's room for companies creating a line of service stations for fast swap and conventional charging with a bank of batteries that meet standard specifications.
Anyway, for daily needs, the current charging time is simply amazing and for sure it will be better in the next years.