12V Battery Question
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Intermediate
Joined: Mar 2023
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From: New York
12V Battery Question
Sorry new to this Hybrid set up, question is their regular car battery in Hybrid like gas car? Can the battery go dead in which you can't start the car like regular gas car?
Intermediate
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From: WA
Driver
Joined: Apr 2022
Posts: 83
Likes: 23
From: BC
Sure, there's both kinds of batteries in there.
One regular battery to basically start the car (mine is in the rear next to the spare tire), this one is charged by the electrical system (like any other ICE vehicle)and
the other larger battery (mine is under the rear seat) can propel the car down the road that the regenerative braking charges.
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Joined: May 2013
Posts: 2,895
Likes: 838
From: Idaho
Sure, there's both kinds of batteries in there.
One regular battery to basically start the car (mine is in the rear next to the spare tire), this one is charged by the electrical system (like any other ICE vehicle)and
the other larger battery (mine is under the rear seat) can propel the car down the road that the regenerative braking charges.
One regular battery to basically start the car (mine is in the rear next to the spare tire), this one is charged by the electrical system (like any other ICE vehicle)and
the other larger battery (mine is under the rear seat) can propel the car down the road that the regenerative braking charges.
Driver
Joined: Apr 2022
Posts: 83
Likes: 23
From: BC
Key Components of a Hybrid Electric Car
Battery (auxiliary): In an electric drive vehicle, the low-voltage auxiliary battery provides electricity to start the car before the traction battery
is engaged; it also powers vehicle accessories.
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Joined: May 2013
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From: Idaho
https://afdc.energy.gov/vehicles/how...%20accessories.
Key Components of a Hybrid Electric Car
Battery (auxiliary): In an electric drive vehicle, the low-voltage auxiliary battery provides electricity to start the car before the traction battery
is engaged; it also powers vehicle accessories.
Key Components of a Hybrid Electric Car
Battery (auxiliary): In an electric drive vehicle, the low-voltage auxiliary battery provides electricity to start the car before the traction battery
is engaged; it also powers vehicle accessories.
https://en.wikipedia.org/wiki/Hybrid_Synergy_Drive
This next link provides a more direct answer, and I have read numerous others supporting this same conclusion: https://mag.toyota.co.uk/coronavirus...r-maintenance/
“To recap, Toyota hybrids generally contain two batteries: a 12-volt battery (which powers systems such as the headlamps and audio) and a high-voltage hybrid system battery (which supplies the power to start the combustion engine and drive the electric motors).”
Here is another general discussion about 12v batteries in hybrids from a manufacturer of replacement traction batteries which also matches my understanding: https://greenbeanbattery.com/hybrid-...two-batteries/
Bottom line: my understanding is the 12v battery on most modern hybrid drivetrains power accessories and lights, and cycle the relay(s) on the traction battery to apply power to MG1 in order to start the ICE.
Last edited by TechNut; Mar 13, 2023 at 09:53 AM.
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Driver
Joined: Apr 2022
Posts: 83
Likes: 23
From: BC
I don’t believe that is accurate for the Toyota/Lexus Synergy hybrid system. I have followed many discussions on this since my first hybrid in 2006 and this is the first time I have read any discussion suggesting the 12v battery starts the Internal Combustion Engine (ICE). You do realize a Toyota hybrid doesn’t have a starter motor? The Motor Generator 1 actually starts the ICE. It would seem to me that a 12V battery would likely be underpowered to spin MG1, not to mention restarting the ICE every time it cycles back on. I have included a description of the Toyota/Lexus system below and I will admit that it does not specifically answer this debate, but it is good background. I simply believe that government report is either wrong or at the very least, too generalized and not applicable to Toyota’s system.
https://en.wikipedia.org/wiki/Hybrid_Synergy_Drive
This next link provides a more direct answer, and I have read numerous others supporting this same conclusion: https://mag.toyota.co.uk/coronavirus...r-maintenance/
“To recap, Toyota hybrids generally contain two batteries: a 12-volt battery (which powers systems such as the headlamps and audio) and a high-voltage hybrid system battery (which supplies the power to start the combustion engine and drive the electric motors).”
Here is another general discussion about 12v batteries in hybrids from a manufacturer of replacement traction batteries which also matches my understanding: https://greenbeanbattery.com/hybrid-...two-batteries/
Bottom line: my understanding is the 12v battery on most modern hybrid drivetrains power accessories and lights, and cycle the relay(s) on the traction battery to apply power to MG1 in order to start the ICE.
https://en.wikipedia.org/wiki/Hybrid_Synergy_Drive
This next link provides a more direct answer, and I have read numerous others supporting this same conclusion: https://mag.toyota.co.uk/coronavirus...r-maintenance/
“To recap, Toyota hybrids generally contain two batteries: a 12-volt battery (which powers systems such as the headlamps and audio) and a high-voltage hybrid system battery (which supplies the power to start the combustion engine and drive the electric motors).”
Here is another general discussion about 12v batteries in hybrids from a manufacturer of replacement traction batteries which also matches my understanding: https://greenbeanbattery.com/hybrid-...two-batteries/
Bottom line: my understanding is the 12v battery on most modern hybrid drivetrains power accessories and lights, and cycle the relay(s) on the traction battery to apply power to MG1 in order to start the ICE.
I own a 450H, it's a detail I never really considered.
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