I don't know guys but the diesel glow plug seed to have been doing the job easily. It got stupid hot but if you do the test on concrete I don't see an issue. One of them (at least the one I used) managed to pull just a little over 15A so I am guessing that you wouldn't need too many to test a lipo properly. I called one wrecking yard and they said that they wanted $85 for one second hand glow plug like the one I used so that wouldn't be feasible. I also called a truck wrecking yard and asked if the had some cheap glow plugs. They said that there are engines out back that I can have the glow plugs from for $10 a piece but I had to remove them my self. Still I am not all that confident doing this nor do I want to destroy any of my batteries so maybe I should leave this kind of testing to those in the know.