"enterprise" disk is just that; it's just disk. I've not seen a disk with an onboard battery. You can put a raid controller in front of your disks, with or without battery backed cache. (most raid cards have an optional battery module.) But, even many gold plated 'corporate' systems I've seen omit the battery, as it's usually not cheap.
My personal opinion is that raid controllers are of little value without battery backed cache.
I just use MD in front of 'enterprise sata' drives, as without doubling my total cost for storage, I can't get a raid card, as far as I can tell, which is better than MD, and really, if I was to double my storage cost, simply buying twice as many spindles would get me better bang for my buck, I think, than a hardware raid card that cost that much.
My personal opinion is that raid controllers are of little value without battery backed cache.
I just use MD in front of 'enterprise sata' drives, as without doubling my total cost for storage, I can't get a raid card, as far as I can tell, which is better than MD, and really, if I was to double my storage cost, simply buying twice as many spindles would get me better bang for my buck, I think, than a hardware raid card that cost that much.