BigKetchup said:
1. They told me that the battery has a 70% warranty until 8 years / 100,000 miles on it, so I'd assume I'm good on that front unless there's something I'm overlooking, but what's the cost of ownership on these cars otherwise?
The battery pack warranty information that you received is correct.
The cost of ownership depends on whether an i3 is a BEV or REx model. BMW recommends replacing the brake fluid of all i3's every 2 years. BMW recommends that U.S. REx owners change the REx engine oil and filter every year. These maintenance tasks could be performed well by any good mechanic including an i3 owner, so the cost depends on who performs these tasks.
The cabin air filters should be replaced periodically, depending on how much one uses climate control and how dirty local air is. I recently checked those on our 2014 i3 recently and they looked quite clean, but our local air is very clean and we haven't used climate control very much, so most i3 owners would need to change these filters more often than me. Again, anyone could change these filters, so the cost depends on who changes the filters and where the filters are purchased.
BigKetchup said:
2. Regarding at-home charging, what products should I purchase? I have a 20-ampere, 120 volt outlet in my garage but not sure if I need to upgrade it. I don't think it comes with an appropriate cable, either, but I've seen some used ones sold on eBay. What can you recommend?
Which EVSE should be used with an EV depends on how far and efficiently an EV is typically driven, how long it could be charged each day, and whether it would be charged elsewhere as well. A 10 A or 12 A @ 120 V Occasional Use Cable (OUC) is included with all new i3's. Driving an average of 4 mi/kWh, an OUC would add ~5 miles of range per hour of charging.
With a 20 A garage outlet, you could buy a 16 A AC Level 1 EVSE which would add ~8 miles of range per hour.
If you live where winters are cold and want to increase your range by preheating your battery pack, an AC Level 1 EVSE would not provide sufficient power to both charge and heat the battery pack simultaneously. Battery pack preheating takes a maximum of 3 hours, so before heating starts, the battery pack would be charged so that an AC Level 1 EVSE could be sufficient.
A problem with relying on a 120 V EVSE would be the repeated plugging/unplugging of the EVSE which could eventually wear and weaken the receptacle's contacts. This would increase the electrical resistance between the plug and receptacle which could generate enough heat to melt the plug and/or receptacle. There have been numerous reports of this occurring.
If a 120 V EVSE might be insufficient for your needs, you'd need to have a 240 V charging circuit installed so that you could charge with a higher-power AC Level 2 EVSE. There are many AC Level 2 EVSE's to choose from, all of them compatible with an i3. The i3's maximum charging current is ~30 A, so to charge as rapidly as possible, an 30 A EVSE connected to a 40 A charging circuit would be needed.
BigKetchup said:
3. Anything else that's not obvious? I'm trading in a 2014 Kia Soul which runs really well actually. So not sure if that's even a good move but I'd like to upgrade to something both more fun and environmentally sound.
All i3's are equipped with low rolling resistance tires of unusual sizes made by only Bridgestone. These tires wear out faster than most tires depending on how aggressively one drives, so the expense of tire replacement would likely be greater than with your Soul.
