Yup I pretty much did what John said above.

The only difference is I used two "Wolfpack" 3800mAh 7.4v packs from Tower wired in series to produce 14.8 volts.

I cut the existing cable from the starter and wired up two Tamaya style connectors for the batteries.

I charge each battery separately on my charger... so I charge the packs up in 2 hours at 1C.

On a typical weekend of flying I use up about 1000 mA on each pack ( or less! ) and that's over 20+ starts, including hard starts, larger planes, etc.

In other words I could theoretically go 1 month between charges if I wanted to... I tend to charge the packs every 2 weeks though.

I had previously purchased the Hobbico 12v battery and container sold by Tower. But I found that the battery would barely last me a season, and the starter was anemic with the battery sold by Tower.

After starting a larger plane, after borrowing a starter from someone at the field, who had done what John is suggesting, I decided to do likewise... there is NO going back now! It's a huge difference..