I tried probably 10 different types of the "traditional" batteries. All had downfalls of one kind or another. Most had really inconsistent power delivery both in the pits and down track. Most couldn't recover fast enough to pulse the solendoids effectively, most couldn't go multiple passes without drop on a volt meter most took quite awhile to bring back to a "full" charge most were damn expensive especially when compared to their lack luster performance and most were as heavy or heavier than the Li drill setups I run.
If your going to try and run a stand alone ignition system the last thing you want to have to question is the power delivery and capabilities of your battery.