Koolstop makes brake pads specifically for electric bikes.

According to http://www.koolstop.com/english/disc_pads.html:

Our E-Bike disc pads are produced with a ceramic barrier between the organic friction material and the steel backing plate to reduce heat transfer into the brake caliper causing brake fade. With the heavier design and quick speeds of Electric bikes, they require a compound that will hold up and provide consistent braking power.

Are they any good?  I couldn’t find any reviews, so of course, I bought a set for my disc brakes (specifically, Kool Stop Deore M525 Disc Brake Pads for Electric Bikes).

Yes, they are very good.

I was making one of my normal “Lots of downhill” runs (to get beer, of course!), and decided that, with the ebike compound in the rear, I’d skip the use of the front brake until I faded the rear.  Normally, I fade the rear if I’m using it alone by the bottom of the first hill.  These kept going solid, and held my speed nicely down several more steep hills (about 300’ of descent combined, all fairly steep).

My rear rotor is shades of blue and yellow from heat.  I didn’t know bike rotors could turn those colors.

I’m genuinely impressed by them.  My caliper remained cool, my brake force remained reasonable, and they gripped nicely, even as the rotor got hot enough to turn colors.

I wholeheartedly suggest them if you’re rocking an ebike in hilly terrain!