It doesn't say 48v maximum. It says for electric bikes up to 48v, but it doesn't qualify that statement, so it's open to interpretation.
I have come across some of this terminology before. The basis as I understand it is that old telecommunications equipement used to operate at voltages up to 48 50 volts.. the lead acid batteries in telephone exchanges were nominally 48v. But when fully charged might be closer to 56v The european low voltage directive allows single insulation for voltages below 50v ac or 70vdc... Above which cabinets need to be locked, and cables have two layers of insulation. This is why for instance loudspeaker connections on domestic hi fi amplifiers are still binding posts and banana connectors.
The directive allows voltages inside equipment to exceed these limits, but no externally accessible connection may exceed the limit. Eg laptops and gamegear video games would have had very high voltages for their flouresent backlights on their lcd displays, prior to leds, and were legal. But the li ion batteries were limited .
In the case of ebikes, even if the battery were to be charged in excess of 48v, but it was impossible to access the live terminals, they would be legal... As an example the Bosch charger and batteries have a communications sequence before the voltage is available.
The 48v standard , even if the voltage within the battery exceeds that level momentarily or occassionally would be seen as compliant. Provided the ebike would work properly at 48v.
What is interesting is that car electrics including starter motors , power steering, turbos are now moving to a 48v standard, with lithium ion battery as the strorage.
