Randy Eckert wrote:
> What about heating the battery pack in the winter... say with those
> wires you wrap your pipes with to keep them from freezing? At least
> while it is at home.
This is a good idea in any climate where you get cool or cold
temperatures. The colder the battery, the lower its capacity. But if you
keep them warm, range in winter can be as good as in summer.
First, insulate the batteries. They generate heat during charging and
use. The insulation traps the heat to keep them warm. In my last EV with
flooded golf cart batteries, 1" of styrafoam insulation was enough to
keep them warm just with the waste heat from daily driving and charging.
If you drive less, have more efficient batteries, or face very cold
temperatures, then heaters will be needed as well. Obviously, the better
your insulation, the less heat you need. There are commercial heating
blankets for batteries. My present EV has a 75 watt battery blanket
heater in each of the two battery boxes.
Plus, people have used all sorts of things for heaters. Electric
blankets from their beds, heating pads, heat tape for pipes, soil
heating wire, etc. Just be careful to protect it from accidental spills
of battery acid and other environmental damage (a car is a rough
environment)!
> I was looking at some of those back up power sources for your PC.
> They have wonderful clean sine wave outputs and built-in battery
> backup...
You must be looking at different ones that I've seen. Most of them have
very low quality output waveforms, because computer power supplies don't
care if it's a sinewave or not. When AC power is available, it just goes
straight to the output; it's a sinewave because the AC input is a
sinewave. But when AC is lost, the output is a "modified sinewave" which
is marketing doubletalk for a square wave with an off-period (zero,
positive, zero, negative).
Many of these inexpensive inverters are also very badly built, and their
specifications are wildly exaggerated. They know full well that the
average customer won't test it, and won't use it more than a few hours
until *after* the warranty has expired.
> That could be upgraded to a 12volt accessory battery to run all your
> 12 volt stuff, plus it would keep those batts charged...
Many of these UPS supplies do not isolate the battery from the AC power
line! If you ground the negative of its 12v battery to you car body,
you'd have a deadly shock hazard when it's plugged into AC!
A second problem is that the UPS battery charger is terrible. It's
usually a low-current float voltage charger that destroys the battery
from chronic overcharging in 2-3 years.
There *are* reliable, high quality inverter/chargers that deliver real
sinewave outputs, have decent chargers. But they cost significantly more.
> How about putting that heat tape inside your car seat?
That could work, too. I think I would look for commercial heated seat
covers, or heated seats that are installed as a factory option in some
cars. This way, all the details have been worked out for you.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
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