rock, the Atrix doesn't really have a battery cover, it has a "rear case" half. And it is not at all obvious but that only fits securely when it is put on in exactly one way only, you sort of have to put it on at the bottom, wok your way up both sides, and then snap the top closed. When done properly it fits very nicely. When done hastily or from the wrong angle, it never seats properly. It isn't at all obvious.
It would be a very odd phone if they added a rubber coating to the back, but not the sides or the entire case. And it would be a thicker phone. I'd suggest you look at the Otterbox Defender, their middle-grade case for this phone. A nice elastomer shell for the whole phone with a hard polycarbonate outer shell. Makes for a grip that feels much better than the naked phone, and substantial protection. Doesn't pick up pocket lint the way a lot of the cheap "rubber" skins do.
Or you can take off the rear case and spray it with "bumper paint". That's a black vinyl rubber spray paint for auto bumpers, a $5 can will "rubberize" all sort of things.
It would be a very odd phone if they added a rubber coating to the back, but not the sides or the entire case. And it would be a thicker phone. I'd suggest you look at the Otterbox Defender, their middle-grade case for this phone. A nice elastomer shell for the whole phone with a hard polycarbonate outer shell. Makes for a grip that feels much better than the naked phone, and substantial protection. Doesn't pick up pocket lint the way a lot of the cheap "rubber" skins do.
Or you can take off the rear case and spray it with "bumper paint". That's a black vinyl rubber spray paint for auto bumpers, a $5 can will "rubberize" all sort of things.