12 volt soldering iron

[brown4s]

I am trying to find a decent 12 volt soldering iron that I can run off a leisure battery if required when racing at my local track.

I can't find any apart from the core 60watt emergency iron that is about £15

Can anyone help or do I just get this and hope that if I need to use it for electric work it will be up to the job.

I did find a weller iron (30 watt I think) that is 12 volt but it's £80 ish quid and I wasn't sure if it would powerful enough plus it wasn't cheap

Let me know if anyone has any suggestions

Cheers