My Background: I'm a regulatory engineer (electronics background). I worked for UL for 21 years and now I work for Snap-on Tools, helping them get cordless tools certified. I looked into the standards for certification requirements.

I found that there are a LOT that goes into safety certifications on an eBike: Bike system, battery and charger are all separate. Tests they do on the bike:

• Input: make sure the input current drawn doesn't exceed ratings
• Temperature: make sure that component temperatures don't exceed their specs. (which is easy to do, if components are under-spec'd or under-cooled)
• Isolation Resistance: measure the resistance of electric insulation to make sure it's adequate
• Dielectric Strength: test the electrical insulation with a high voltage to make sure it's adequate; doesn't arc
• Humidity Conditioning: Same as Dielectric, but after a humidity soak. (humidity can penetrate certain materials and reduce the insulation properties)
• Abnormal Conditions:
  • Overcharging
  • Component Faults
  • Blocked Ventilation
  • Locked rotor: Lock the motor up and confirm no fire, explosion, concentration of flammable gas, etc.
  • Running Overload: gradually overload the motor and confirm no fire, etc.
  • Battery short circuit
  • Imbalanced charging: This is an important one. There are dozens of cells in the pack they go out of balance over time and then when the charger charges to the same pack voltage, it means that the other cells in the pack are overcharged as a result of the tired cells not reaching their full voltage.
  • Shock: (kind of an impact test)
  • Thermal cycling: Confirming nothing bad happens when the bike is moved from a cold environment and back
• Impact
• Mold Stress: Makes sure the molded parts don't distort and expose anything that should be enclosed under hot conditions
• Flexing: checking wire harnesses to make sure they're rugged & reliable
• Ingress protection (IP testing) for dust and moisture; make sure safety-critical electrical spacings aren't effected
• Vibration: Checking the effects of shipping. You'd be surprised how many components will shake off a board in this test. Usually big capacitors and inductors that aren't glued down
• Strain Relief: Check that if a cord or harness is pulled, it can protect the electrical connections from the strain
• Startup Assistance Mode: confirms max 6 kph (3.7 mph) in walk mode and that it self-cancels if the button is released

The battery cells have to be certified on their own. Then, they are certified in the pack and again in a certified bike.

The chargers have their own requirements.

This is a big expense, but they really do make the bikes safer.

I remember when cheap Chinese hoverboards were burning houses down. The US government approached UL and asked them to write a standard so they could require it. Now that eBikes/batteries are burning down shops in NYC, there is a standard for electrical systems for eBikes (UL 2849) as well as for the battery packs for use in light electric vehicles (UL 2271).