Just recently found myself in this predicament when replaying the career mode on hard. I found that Right-clicking on the engine and dropping the output down as low as you can without zero, you can put in about 10% throttle, get a roll started, then shut it off and wait. Bring in throttle to stop roll. Re-adjust output for the entry burn, and you're fine... some what. This mostly works with gimbled engines like the Terrier (no alternator) and the Swivel (alternator) Level 1+ pilots can still align with the gimble engines and no battery using SAS directions. Just remember they need active engines to do those SAS commands if no battery...
Now, if you're using the non-gimble Reliant (I think that's what its called... ) you'll have to drop engine output, fire it up to charge battery, then use small inputs to the gyros to get attitude change started. Just keep the SAS turned off, and pay close attention to your orbit changes. Transmitting data will KILL all progress, so just save the data, recover it on land, and be thankful for small science...
There IS life after battery... ... and yes, your parachutes will still deploy without battery.