EarthX Battery

Sure it is battery related? I have a shorai. It doesn't start when cold. Does the earth x?

I know yammy riders that have had coldstart issues with the Shorai and Earth X when it gets close to 0F. Jumper time, or take the battery out at night, or put a heat source on it before you start. Don't know of runability issues with them. Injectors operate off a different VR circuit, rectifier, and stator, I believe, than the charging circuit. Can't speak to the injector problem that you experienced, tho.

battery

There is a video [ somewhere on here] that shows the proper way to start a cold engine using a lithium battery. They start a Harley in freezing weather.
The battery needs to be warmed up, but you use the starter to do it. It took 4-5 short starter hits then the bike fired right up.

Earth X

We were just in Seeley Lake and it was -18 degrees one morning.

My wifes Apex with the largest Earth X model would turn over but not enough to start. Even after a couple flicks of the key it didn't seem to be kicking in. I had a small battery charger with that also has the start mode and by hooking that up it in that mode it had enough juice to start.

My 2013 Pro has electric start. Tried 3 short bursts to get it going. No luck. Tried pulling it over and I knew that would be a last resort. Too hard. Went back to room to consult manual and then learned you can give it quarter throttle to aid cold starting.

Anyway by the time I had walked back to it while Apex was warming up, it started at the flick of the key. Not sure why but that's my experience with a Li-on battery and my AGM battery in the Polaris.

If Polaris had standardized on the battery size like the old Edge/wheeler sized batteries, I would change the AGM out for Li-on and use the battery year round between the wheeler and snowmobile.

I like not worrying about loss of charge over time in the Li-on vs. the AGM batteries.

Lithium batteries need to be warmed. You can do this buy drawing a small charge or warming the battery. When I built my Nytro I put handwarmers on the battery, so I could always heat it on cold cold days before I needed the cranking amps.

The battery ended up just totally crapping out for no reason and decided the weight and cost was not worth it. I dropped 100lbs on the Nytro, so I took weight pretty seriously.