Lithium Iron Phosphate or LiFePo4 Battery for Nissan Skyline GT-R

Update 3-2-2020: Battery still works, cranks fast, haven't had it on a tender. Even if it sits for a month or more, fires right up.

Update 4-24-2020. I think I left the trunk open for a week or two, and I flattened the battery. I pushed the button, it barely lit up. Car did not start, or have reserve power. Put a normal jump box on it, started right up. Left it running about 10 minutes, battery seemed to be fine. Started right up. Left it for a few days, and started right up.

The battery in a Nissan Skyline GT-R - R32 version is located under the hood, in the right front corner. It uses JIS, also called pencil post, battery terminals, which are smaller than the normal SAE terminals we normally see in the US.

The OEM size is a 40B19R. The OEM batteries have about 330-370 CCA. and are lead acid. While looking on eBay one day, I noticed these lithium iron phosphate or LiFePo4 40B19R batteries with 550 CCA.

Their were two styles, one with a built in "jump start" accessory, and a normal one. The claimed weight was just about 10 lbs. I weighed a 40B19R that I had, and it weighed in at 18 lbs while a S46B24R (Prius battery) came in at 28.8 lbs.

Lithium Iron Phosphate or LiFePo4 Battery for Nissan Skyline GT-R

Lithium Ion batteries have a reputation as being a bit temperamental. They require specific chargers, and can't be run down on battery power. They can go postal on you. LiFePo4 batteries are slightly different but supposedly slightly more forgiving. So the question was going to be, is it worth it? A normal Prius type battery is anywhere from about $170 to $250, and these came in around $350. So $100-$180 more, is it worth the 10 lb weight loss? If you are racing, then that 10 lbs is worth it all day, every day. However for a street car/limited track car, do the hassles out weigh the potential hassles and/or hazards?

Lithium Iron Phosphate or LiFePo4 Battery for Nissan Skyline GT-R

The LiFePo4 battery requires a specific charger/tender in order to not overcharge or damage it. I bought a Battery Tender that will trickle charge the battery if it needs it. Once it came, I weighed it, and it was slighter heavier than the documentation coming in just under 12 lbs. But 6 lbs is 6 lbs.

Lithium Iron Phosphate or LiFePo4 Battery for Nissan Skyline GT-R

Now the question was going to be how long, and how will I test it before I write anything about it? The battery fit easily, but the power button, and the voltage gauge were slightly obstructed by the battery tie down. The battery itself is small and light. Very obvious when you pick it up. Had a built in handle making putting it in even easier.

First start, I noticed the #bluecar cranked a bit faster than before. Everything seemed pretty normal. Charging seemed normal. Let the car run a while, and checked voltage after turning it off. About 13.8 volts. Couple more starts verified to me that it spun over quicker and seemed to light off a bit quicker.

The question then was how should I test out the jump section? I wanted to run the car down to nothing, then see if I could start it. However if it didn't work, and I killed a $350 battery, I was going to be pissed off. So instead, I plugged in the tender and let it sit overnight, everything seemed normal. Then I figured, I will leave it off the tender, see how it handles life. If it dies, it dies, then I will get a chance to use the jump side. The battery was installed on June 29th, 2019. 169 days so far. The #bluecar doesn't get driven too much, some occasional weekends, some R's Day's. So far nothing negative to say. Car starts every time. The battery hasn't melted down, nor failed. Even with one track day under its belt.