Caution, noob ahead, I have lots to learn! I want to make a very bright spotlight. I got a 75W HID and ballast off of ebay but I am having trouble powering it. If I hook it up to a couple of lead-acid gel cells (feeding it 12V) it lights up very well. I want to run it off of rechargeable lithium's. I tried hooking it up to 8 18650's but I only get a single flash it will not run. What do I need to power this thing?