12 volt battery replacement for 2010 Prius III

There are safety reasons you do not want the wrong battery. (If you never drive anyone but yourself, then safety is personal choice)
You want a AGM battery to minimize the amount of sulphuric acid in the passenger compartment with your passengers.
You want an externally vented battery to minimize the amount of hydrogen gas in the passenger compartment with your passengers.
You want a battery with the positive terminal as far from the steel body of the car as possible, to prevent heat that would result in the case exploding or outgassing.

Now at a more convenient level, the stock battery has JIS posts that are rare and sits in a hole that does not allow a larger battery.

Toyota's replacement battery currently has a 84 month warranty, which can be a compelling reason to get it.
The first company to offer an aftermarket Prius battery (Gen 2, Gen 3, v, and PiP) was Optima
Optima DS46B24R Optima battery direct fit replacement for Prius 2004 + , Prius v & Plug-in Prius with Instructions
Other Prius batteries also exist now
Exide AGM Car Battery (Group S46B24R)
Super Start Platinum PRIUS - Battery | O'Reilly Auto Parts
http://www.napaonline.com/Catalog/CatalogItemDetail.aspx/Battery-NAPA-Legend-75-Month/_/R-NBE9851P_0396636574
You basically want any Group Size S46B24R battery

 

How long ago since replacement? Year and mileage of car? Optima is a deep cycle aftermarket battery.

There is no reason a jump start wouldn't work if it's a 12v battery issue

 

Sometimes a really discharged 12v battery needs to have the jump start / charger sitting on the jump terminals for five or ten minutes to somewhat charge the discharged battery. Otherwise the deep discharge of the battery keeps the voltage down too low.

Also, it is IMPORTANT to find out why the battery discharged! It will happen again on a new battery. What I found was the rear hatch light will stay on if the hatch is not closed all the way. All the other lights are on a timer. So I replaced the rear hatch light with a led version AND keep it off at the light's switch. It is nearly useless anyway.

Finally living in warm weather states as we do, your current battery may be ok, especially in a 2010. I have an 08 that had three discharges on the 12v but still has the original battery. My 2012 has never had a 12v discharge.

 

If you are jump starting the car battery, I don't think the dead battery comes into play at all. It uses the power from the jump start car/battery, not the dead battery in the car. After the car starts, it's up to the car's electronics to keep the car running while charging the dead battery.

 

i suppose a marine battery will put up with the deep discharges.

 

The Toyota OEM has a nice long warranty -- great for people who wreck them with accidental deep discharges.

 

Huh? Explain, please.

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You don't want to short the battery by somehow having the positive terminal grounded to the body of the car. The car body is directly connected to the negative terminal as the ground.

 

Obviously. However, that's a long way from claiming you must have the "positive terminal as far from the steel body of the car as possible, to prevent heat that would result in the case exploding or outgassing ..."

 

That was my first thought too but it depends on HOW the old battery has failed.......and maybe what is being used to jump with.
IF a cell has shorted, a portable jump device might not have enough power to overcome that.

A multi-meter and battery charger would help tell a much better story.