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Will the car be DC or AC and why?
What components are you planning to use?
How many volts will be used and how did you arrive at that number?
Why Optima batteries over golf cart style batteries?
Why use a Manzanita Micro charger?
The car I owned when deciding to build an electric was too heavy to convert. This allowed me to look at what was available (inexpensively, of course) to use for a conversion. I decided on the Miata because:
* They’re light which means less mass for an electric motor to move around
* They are aerodynamic, which helps at freeway speed
* Most have manual transmissions, which is required for an electric conversion
* Being a convertible, in most climates they don’t need air-conditioning.
* Most are well cared for - they were an "IT" car that some people gladly paid a premium for
* Parts are easily available, including body kits, low profile headlights, even kit cars
* You can find them in good shape inexpensively
* Their styling is classic, some say iconic
* They are a blast to drive!
Range data that I have been able to find is very subjective, so I don’t have a number I can quote today. I will be happy with 40 miles, but think it may be closer to 30. My commute is short, so range wasn’t a key factor in my choice of components. I plan to do some testing when the car is complete to get an accurate range estimate.
Real safe. First, I have heard that a gallon of gas is equivalent to 13 sticks of dynamite. Kind of puts things in context, don't it?
Anyway, to start with, we have a car that met federal safety standards that were in effect at the time it was made. So it has driver side airbag, crumple zones, steel rails in the doors and all those kind of things.
As for the conversion, the battery racks fully enclose the batteries and are securely bolted to the frame rails, so the batteries won't fly out of the car in an accident. The batteries are also Absorbed Glass Matt (AGM) type that won't leak or splash acid even if punctured. The Controller has a number of safety features that disable the battery pack on over heating, a stall or an internal error. Plus the pack is fused and is planned to have a circuit breaker that the driver can shut down in an emergency.
The car will be DC. AC provides regenerative braking and higher range, but at a much higher cost and with fewer choices of components. DC also provides better acceleration, which is a key criteria for the car.
9” WarP, Zilla 1k, Manzanita Micro charger, Iota DC to DC Converter and 13 Optima Batteries
The 9” is more efficient than an 8”, plus, I’m optimizing the car more toward performance than range or cost. The larger motor will provide better performance.
The Zillas are more efficient than the other controllers available today, plus they have additional safety features and controls.
The car will use 13 12 volt Optimas for a total of 156 Volts. I could physically get 16 batteries in the car for 192 volts, but that would require a more expensive, higher model Zilla. I decided on 156 volts because it was the maximum voltage the low end Zilla could support.
While golf cart batteries are definitely cheaper, they don’t provide the performance of more modern batteries like Optima, Hawkers or Orbitals. Furthermore, they require watering, off gas Hydrogen – so they need to be vented and enclosed, and, in an accident can splash acid. The Optimas are AGM (Absorbed Glass Mat) batteries that don’t require maintenance, don’t off-gas and won’t leak or splash acid if cracked open. They do require a BMS (Battery management System) for charging, but that that’s a small price to pay for safety and performance.
I wanted to use 220v charging at home and still have 110 for opportunity charging while on the road. I was planning on using 2 chargers – a 220 Zivan mounted in the garage at home and a 110 Zivan in the car. This dual charger arrangement created complexities, and didn’t save much money or weight. I decided to simplify and stick with a single on-board charger that would handle both 220 and 110 voltages. Plus, the Manzanita Micro charges are designed to work with a BMS system that Manzanita also makes. I may be spending a little more for this combo of charger and BMS, but the batteries aren't cheap so they aren't a place to cut corners.
