Battery Tender 12 V Lithium Iron BTL14A240C #900656

I know this is a motorcycle / ATV application but I put this battery in my stree and autocross driven Miata. So far it cranks strong and has had no trouble starting the car. It has saved somewhere around 20 pounds and is only a little heavier than an AGM battery of comparable output. I had to fabricate a bracket to mount it rigidly because the original hold - down wouldn't work. It's too small to get any clamping on the battery. Also, I left the terminal post rings on the wires and replaced the lead screws with the supplied screws to connect to the terminals. This is a little awkward to connect but allows me to go back to an AGM battery in the future if needed. Because both terminal rings now face toward the trunk interior I am a little concerned about an accidental short, so I wrapped the negative one in electrical tape and modified the positive rubber factory cover so it would still give some protection.

I was concerned 240 ca battery was too small but it cranks over a high compression Buell Ulysses with no problem! You'll swear the box is empty because the battery is that light! If you are into weight savings, this is the battery for you. Now let's see how long it lasts....