So, I think what you’re saying is that there’s no good e-bike standard protocol to which manufacturers can adhere and report important electrical data? Or, is there another protocol other than ANT?
The only widely accepted standard is ANT+ with the LEV extension. The implementation of ANT+ for a given e-bike system solely depends on good will of the e-bike system manufacturer. For instance, Wahoo has no issue to recognize both Main and Range Extender batteries while Giant/Yamaha battery is not being recognized because of some software glitch on one of the sides. While Garmin will read the Giant battery but not recognize any Range Extender. Wahoo intercepts the Travel Mode name (ECO, SPORT, TURBO etc as it has been written in the e-bike software while Garmin can only produce 1, 2, 3...
Bosch E-Bike is the major brand that staunchly ignores the very existence of ANT+ (for that reason I won't buy a Bosch powered e-bike).
Any premium e-bike brand has their own service app that communicates with the e-bike by Bluetooth. Such a protocol is proprietary and can produce almost any e-bike parameter on your smartphone if the manufacturer wishes so. Let me give you an example from near past.
The first generation of modern Specialized e-bikes had its own app called Mission Control. Meanwhile, an Italian guy by name of Paolo Dozio wrote his own Bluetooth app called BLEvo. BLEvo was a genius app capable to extract any existing Turbo e-bike parameter to your phone, including fields reserved by Specialized for future purposes. You could for example read the
actual capacity of your batteries, motor and battery temperature along with the current motor current and voltage, electrical motor power, the ratio of rider power to motor power, and some 50 other parameters. BLEvo could also reliably calculate the Remaining Range! You could even set the assistance in 1% increments! BLEvo was a danger for Specialized, as it revealed uncomfortable facts such as a brand new battery might have a way lower capacity than declared or that the batteries were significantly degrading over their use. So Specialized introduced a new system called Mastermind and
encrypted the Bluetooth channel*, rendering BLEvo unusable for newer e-bike models. Now, Specialized only shows you what it wants to show in its new Specialized App. End of the story.
(My both Specialized e-bikes are older models so I can still enjoy using BLEvo if I need).
Re-iterating: LEV ANT+ is the e-bike MIDI but it hasn't achieved the excellence level or recognition similar to MIDI. However, it is not any dead-end as illustrated by the fact TQ HPR system is equipped with the protocol. ANT+ is a transmit only protocol, so nobody can manipulate their e-bike with that protocol (it was possible with unencrypted Bluetooth).
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*) Perhaps because of EU RED regulation described by
@mschwett.