Every LiPoly is rated with a C rating, which is marked right on the battery's label, but if you're using NiCds/NiMHs, things are unfortunately a little murky... Because NiCd/NiMH cells are not manufactured for R/C use, the manufacturers rate them based on industrial/commercial applications where they need to be dependable and last for years. If we stuck with the manufacturers' recommendations on current for NiCd/NiMH, we'd still be in an electric "stone age."

In fact, we push our NiCds/NiMHs much harder than the manufacturers would like to see, and the REAL current limitations were determined by some very ambitious and generous modelers who literally blew up packs to see how much they could take at their own expense. The limits aren't widely published; in fact, the only vendor I know of who publishes them is cheapbatterypacks.com. Most limits are "published" in a forum setting like this, and as you hang around for a while, you'll get a feel for what they are. I've got many of them committed to memory, myself.

One general rule of thumb is, the shorter and fatter the cell, the more current it can produce. I'm guessing your 1100mAh NiCds are AA size. AA cells generally don't make good R/C flight packs because they're designed for capacity, not current-delivering capability, and the fact that yours come back uncomfortably hot indicates that you're pushing them too hard. I believe AA NiCd cells are pretty much limited to 8-10 Amps.

Depending on the manufacturer of the cell, a "2/3A size" 1100mAh NiMH is good for 12-15 Amps.