12v battery

I agree with Jayman, that the VDC harness with plug can be attached to the battery permanently and the charger plugged in when it is needed.

Some of you may think this is overkill but I am using, in addition to the VDC, another method to keep my battery healthy at the -20 to -40 degree temperatures we have up here in the Canadian north. Batteries just do not like really cold temperatures. To produce current at the plates there is a chemical reaction that is hugely inhibited by very low temps. Battery stores sell a "battery warmer" which is a little plastic electric "battery blanket" which you wrap and tie around the outside of the battery. It is 120 volts and comes with a cord plenty long enough to be run with the VDC harness under the rear hatch to stick out 3 or 4 inches to be plugged in when it is below 0 degrees F. I am not sure what it draws but it is just a warmer and is probably about 150 watts.

When I use the warmer and the VDC I never have problems no matter how cold it is outside. A warm battery is a happy battery. The opposite is true also.

 

I use a battery warmer on the diesel tractor at my hobby farm, and the Ford plow truck. Around here most are rated in the 50-80 watt range, at least those of the Philips-Temro brand

If you have to park outside or in an unheated space, the battery warmer makes a huge difference especially in temps of -30 C and colder

 

i have a question for everyone who has been reading about the 12v battery. Isn't charging the 12v with a 10amp charger dangerous?

my battery is clearly labeled that you should never exceed 4.3 (i think it's .3) amps while charging. i just found that today. anyone else have that label? it's in yellow.. below the + terminal.

 

I don't believe so. The 10 Amp spec is a maximum capacity, but depending on battery status that much current will flow just very shortly in a depleted state. Electronic chargers limit the volt output to the saturation level of 12Volt batteries. Once voltage is at nominal levels, the chargers voltage limit will reduce current to nominal levels. Data on these labels specify long term limits to avoid damage by crude methods, usually.
Also, I don't see that the internal converter would limit its output to 4.3 Amps, there was no way to supply enough energy to the 12 V system if it did...

frosh
sidenote:
Probably, if one cell inside the battery is shourtcut, higher current could do serious damage to the other 5 cells and i.e. cause leakage. Under this condition, this limit would prevent a major desaster...

 

That's my + terminal. "never add water nor charge quickly. when you charge battery, charging current should not be higher than 4.2amps and charging time should be within 10 hours"...

 

Yep I recall my Prius also has the scary label. That said - I covered this in your other post - the Prius PDI clearly states to use the Toyota Automatic Battery Charger set to 10 amp position

There really isn't anything special about the fancy schmancy Toyota charger. It's made by Associated and any good auto battery charger will work. Manual chargers should only be used by folks who know how to use them properly, eg to avoid overcharging and battery damage

The Prius PDI also suggests *not* to use the 2 amp setting, as it may result in "prolonged charging time."