How can I charge the 12V battery faster on a Toyota Prius 2007?

yes. The car in Ready can charge at a rate of up to 100 amps. The charging logic combined with the battery state of charge will ramp it down slowly to a low maintenance rate of charge.

On the other hand, if you simply put a small maintenance charger of it, a discharged battery could take ten hours or longer.

A worn out battery can appear to charge quickly from a voltage standpoint because it has little capacity left. It will also discharge much much faster. A battery load tester can determine if the battery has low capacity, not a voltmeter.

 

The battery charges in normal conditions for 10 hours and this is correct.

Because the charging current is calculated and if it is exceeded, the battery quickly fails.

The 2007 battery, due to its age, has long required replacement.

 

No.

 

That's an interesting question.
FWIW
Charging too quickly will induce heat (and boiling).
So my first response is to look at the charge rate of your charger.
2-4 amps is conservative and safe, 10 is extreme. 20 I'd say is for "emergency" use.
I would not leave a 10 or 20 hooked up overnight.

My second question is why?
First guess is that if the battery is not holding a charge, it is battery replacement time.
Second, it may be the car sits for months at a time.

And, make sure your charger to battery connections (and battery terminals) are clean and firm... no debris buildup

My overall comment would be to always hook the car up to a Battery Tender, in an attempt to keep a full charge at all parked times.

Good luck

 

I agree with Kenny, charging an AGM battery fast is not a good idea. And the prius 12V battery is basically for booting up the systems so if it needs that much of a charge it is going to need replacement very soon. But if replacement is going to be a problem a couple of hours on the charger then driving for the day then back on the charger works too.

 

I find with battery in good condition it takes maybe 4 hours before my (~4 amp rated) charger settles into maintenance mode. With a near-depleted one maybe 10 hours. This is overnight doable; I don’t see it as onerous.

 

Once the car is in READY it doesn't matter what else it does. Moving fast is no better than moving at a crawl or not at all. In terms of "driving" there doesn't even need to be anybody in the car as long as it is in park and stays in READY. The gas motor will turn on and off by itself as needed. The 12V is charged by the inverter using power from the high voltage pack. This is different than for a car with an alternator, where the charging rate goes up with the RPMs. Those cars charge fastest on the highway, or around town, if kept in a lower gear. This is why when a mechanic tells you to go drive your Prius on the highway to charge up the 12V you know that you need to find a different mechanic for that car.

 

You really don't want to leave a hybrid in Ready unattended. Drive it.

 

Well yes, there is the chance somebody could get in it and drive it away. Or it might suffer some catastrophic failure with no one present to shut it off. But sitting in it listening to the radio would suffice. There is no reason to take it out on the street just to charge the 12V. Not in a closed space, obviously. Don't want to gas the driver when the engine starts up.