Re: General Discussions
Reply #1811 –
All batteries are charged with DC, whether the charge circuit converts DC to DC or AC to DC makes no difference, most EV cars have smart sockets for both AC or DC charging. DC can mean CW(Constant Wattage, Constant Current, Constant Voltage) or Pulsed dependant on the charger design, but it's all DC. Some modulate power by varying voltage, others use PWM(Pulse Width Modulation.), many use a mix of both to recharge and condition batteries electrodes at the same time.
If you have a 12v / 240v inverter, you can use a 12v source like a lead acid battery to charge your EV enough to get it to a charge station. You could use jumper cables to run an inverter off the idling petrol or diesel vehicle, and the outback charge stations are often just diesel generators which have an integrated 240v inverter, coin or credit card operated of course, and which of course completely invalidates the carbon neutral use of an EV.
Most portable SolarPV won't have anywhere near the power to give any useful range via an inverter, at least not in a single day of charging, it would be like trying to warm your bath water with a candle. The best rooftop SolarPV panels are much more efficient than the portables and yet roof top panels typically only deliver a few hundred watts each day, I think the very best make it to about 650 Watts in a perfect conditions. Good portable panels are about 50% of the solid roof top variety. Your EV battery and motors are measured in tens of Kilowatts, I think a low end Tesla is in the order of 60 ~ 70Kw!
An interesting point, it you bolted a solid SolarPV to the roof of your Tesla in a weird attempt to extend the range, you would actually lose range, because the weight and drag of the panel more than offsets the energy it creates.