Yamaha F70. What size lithium starting battery do I need?

2021 Yamaha 70 hp. Console steer, 18ft Polarcraft.

Does anyone know, from experience, what size lithium starting battery I’ll need?

Call yamaha first to be sure you can.

X2 usually a big no no for starting batteries. I know it voids warranty on some brands.

Didn’t even realize they made lithium starting batteries.

It has to be a starting lithium battery first and foremost. Iconic makes them and a few others. The one I own is a 125 AH and it will put out 1100 CCA. It is over kill but I would rather go big then to be sorry later. My motor is a 60HP and is long out of warranty. I plan to charge it with my 10Amp NOCO at the end of the day.

This is off of the website that sells them: This battery can be used as a starter battery for 250 hp Yamaha or Mercury motors

gim wrote:

Didn’t even realize they made lithium starting batteries.

Myself as well, I just always heard it was a big no-go too.

Those with experience please post your results and what battery/outboard.

Most of my stuff is a decade or more out of warranty

It’s called out-of-pocket now

I have a 22 Yamaha 150. I called Yamaha last year to ask about lithiums for starting/house battery combo. I was told it’s a no go still for Yamahas.

They have been using them for years without issue. You just need to make sure your lith battery is rated for use as a starting battery with the BMS needed, not all are.
You also need a charger with at the minimum an AGM setting for charging. Ionic has one of the better batteries for this, but there are many others now. Relion is another main player.
There are also now many other lower priced options out there.
Technically Mercury is the only one approving them yet, but they also are the only outboard manufacture involved with a lith battery manufacture. Mercury’s and Yamahas have the same basic charging system.
Even before Mercury approved them, you could order out a Ranger walleye boat, from the factory, with not only lith trolling motor batteries, but also a lith starting battery. Go figure.
Go on Bass boat central and you will find the bass guys have been running the lith batteries for years without issue. The only real problems that have been shown are with having the correct onboard charger, using a cheap battery with questionable BMS, or those that have powerpole charging systems, but I think they are slowly figuring that out.
Your better lith batteries have designed their BMS protections to be fully compatible. It is a never changing game though with the newer engines having stronger and stronger charging systems in that they have to keep tweeking the BMS to be able to handle this increased charging rates. I think the future will be a BMS that can be continually upgraded by bluetooth.
Edit, I forgot to add there is one other actual issue, and that is cold temps. If you are one that fishes in cold weather, below freezing, you will have an issue with some lith batteries when charging, and when your engine fires up as it is trying to charge the battery. They don’t like being charged below about 28 deg or so and will shutdown if not designed for it. Your better batteries have options now with built in heaters, and BMS systems where if trying to charge or starting your engine, it will automatically sense the temperature, turn on the battery heater, and not allow any charging till the battery warms up to above freezing. This probably is the one thing that still bothers Yamaha, but there are more and more batteries available now with these heaters and BMS for that. So if you fish when its below freezing in the morning, you need a battery designed for that.
Alot of people don’t realize that with an electric car, there actually are the same issues with cold temperatures. They actually have heaters in them that automatically heat the batteries in cold weather. So you park your car at night and it says say you have 150 miles range left, but you get up in the morning and you only have 100 miles range left, thats because the battery heater ran most of the night.

I have ran an Ionic for going on 4 years with zero complaints! I got sick of running my batteries low with a couple 12″ screens. Now with my 125AH ionic I never even think twice about getting a low battery.

Jeffrey Trapp wrote:

I have ran an Ionic for going on 4 years with zero complaints! I got sick of running my batteries low with a couple 12″ screens. Now with my 125AH ionic I never even think twice about getting a low battery.

Jeffrey, for clarification, are you using the 125AH ionic as your cranking battery?

What outboard motor?

There also is another advantage to your lith batteries. Not only do the better ones such as the Ionic 125 have immense capacity, most good lith batteries have a 10-11 yr warranty. If you are getting one to replace one you have, keep your existing one to put back in your boat if ever selling as the lith one will last so long.
Also you might want to have a jump pack with a wake up feature just in case for some reason your lith battery goes into protection mode for some reason. Nocos have it, my Gooloo also does. The Gooloo packs are only about $70-$100 on Amazon.

4-5 years on ionic 125 ah starting a 90hp suzuki 4stroke and powering 2 10″ screens w livescope

I have a 200 HP Pro XS mercury. Below is a link the the battery I use. I bought one with the heater but I am not sure it is needed or not.

https://lithiumhub.com/product/12v-125ah-dual-purpose-starter-lithium-deep-cycle-battery-with-heater/