Batteries and how long they last:
In simple terms:
The power and longevity of a battery is noted by its Amp Hour (Ah) rating. Basically, this denotes how long a battery will last if it isn’t recharged. For example if a battery is rated as, say 8Ah, it will be able to provide 4 amps for 2 hours. If a battery is rated as 100Ah, it will produce 100 Amps for 1 hour.
No idea what battery a mobility scooter uses, but as a comparison, On average, a car battery can maintain about 5amps for ten hours. That makes such a battery a 50amp hour battery. That is equal to around 600-watt hours
As an example, an iPhone 12 uses a 2000 (ish) mAh battery –  1000 mAh is equal to a 1 Amp Hour (AH) rating so the mobility scooter battery will not go flat by the phone charging as the phone will use 2 amps of the 50 from the mobility scooter battery per charge (ish)
Hope that helps 
In a completely sane world, madness is the only freedom (J.G.Ballard).
You need to login in order to vote