Optima battery not available for 2017 Prius V?

I doubt Toyota changed the battery. There are indications that if the 2018 Prius v comes to the US it will be basically unchanged too.
My son enjoys his 2015 Prius v.

 

Do you need to replace it already? Your car is still under warranty.

 

Yeah.
Warranty would not cover that (ab)use.

 

I am not sure. Would it make sense to have 2 batteries in parallel to increase the capacity?
Our experimenter @bwilson4web might have some insights on the issues doing that. I know he ran a 1000w inverter on an older Prius many years ago,

 

Think I would run two batteries with a marine battery isolator / combiner. This would allow you to run your offline loads with a large capacity deep cycle marine battery and still have the Prius battery for it's intended purposes. Some isolators will allow more than one battery. A good battery box for the second battery would be desirable maybe vented with a tee off the Prius battery vent hose.

The lowest cost isolators are diode based and cause the secondary battery to receive lower charging voltages. A full electronic isolator costs more but will work better. Some models will allow a temporary switchover to jump start the Prus should the primary battery fail. As a result, you could keep the factory battery until it was really necessary to replace.

An easy to get isolator is

 

I was concerned with possibly overloading the Prius inverter when charging more than one battery.

 

Do you also have a 2013 Prius v Five? If not, you may want to update your profile here.

 

The inverter will protect itself from overcurrent. The reality is that a deep discharge on your primary car battery causes just as high charging currents PLUS you have limited amp-hours with the factory battery to start with since it is smaller than normal. On top of that, you are potentially losing hybrid tuning parameters plus you are risking expensive hybrid system damage if you have to jump start the car. A properly installed isolator allows you to fix those problems.

A secondary Marine Deep Discharge battery is designed for your kind of application and will likely last longer than a small Prius battery. When it does need replacement, you can find one anywhere.

 

oh, for shame, draining a car battery repeatedly to a voltage that low would certainly do it in prematurely. I would prefer a voltage no lower than 12.2 volts, before it recharges, if you want a long lifespan. The Toyota battery is pretty small for constant inverter use. Perhaps, a second battery should be added with an RV battery isolation relay for the inverter.