Yes, the GM and Honda are working together on autonomous vehicles, and before that they were supposed to be developing batteries together. However, GM was curiously absent from the reports about Honda teaming up with NASA and Caltech to develop a new Fluoride-Ion battery technology.
My claim is that there has never been any hint that GM provided technology to Honda for the Clarity Plug-In Hybrid. Here's how
Green Car Reports describes the operation of the 1st and 2nd gen Volts, neither of which operates like the Clarity PHEV:
But while GM hasn't explicitly said so, [the 2016 Volt is] no longer as much of a range-extended electric car (or "series hybrid").
The new 2016 Volt should be viewed as a more conventional plug-in hybrid, with engine torque now being sent to the wheels through a mechanical connection whenever the engine is on.
The 2011-2015 Volt has one motor that powers the wheels, and a second that acts as an engine-driven generator to produce electricity when battery capacity is depleted.
The 2016 Volt, on the other hand, has a pair of motors that are roughly the same size, one or both of which can power the car.
It still operates exclusively in all-electric mode up to its range of 50 miles or so (except in very cold weather) before the engine switches on.
But once the battery is down to its "depleted" level, the engine switches on--and it contributes torque to drive the wheels far more often now than it did in the first Volt, when it would clutch into the drivetrain only in a limited set of high-speed driving circumstances.