Is my at-house 240v / 15 AMP Charger AC or DC ?

It is AC.

The only time DC comes into play is if you are using a DC fast charger (Electrify America, ChargePoint, EVgo, etc).

 

Technically, the device is called electric vehicle supply equipment or EVSE. It is AC to your vehicle. The car is equipped with a built-in charger that takes the 240 volts AC from the EVSE and converts it to DC.

See SAE J1772 https://en.wikipedia.org/wiki/SAE_J1772

 

Hey Tim
Your home 240V charger is AC and typically a roadside fast charger is DC. Most folks set the DC charge limit to 80% only because the charge profile slows down significantly after that and if your paying for your DC charge by the minute your quickest and most economical charge happens before 80%. Set your AC charge to whatever suits your need for range. I typically set if for 80% if I am just tooling around town and up to 100% if I am going on a trip and I will need all my range.

 

A pandemic-related footnote:
If the car is not driven regularly, i.e., sitting around for days, then the battery is happiest at 40 - 60% state of charge.

Sent from my Pixel 3a using Tapatalk

 

The Kona does battery balancing at 100% charge. It is a good practice to do a 100% occasionally. I do this about 1 a month minimum but also anytime I need to drive to the Kona's range limit. Battery balancing is necessary to bring all charge states to an equal state. This helps take some of the stress of cells that have different internal resistance. Techie but important occasionally. I generally charge anywhere below 80 miles range to 80%. Don't think you will damage the batteries if you cannot follow the strict 80% limit. These are best practices. These will help you keep you batteries healthy long after the car wears out. Another helpful practice is to DC fast charge only when necessary like when traveling long distances.