12V Car Battery Amps: How Much Current Generated?

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Discussion Overview

The discussion centers around the current generated by a standard 12V car battery, particularly in relation to its application in starting vehicles and connecting to motors. Participants explore various aspects of car battery specifications, motor connections, and the concept of magnetic motors and generators.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants mention "cold cranking amps" as a critical measurement for starting vehicles, with historical values around 350 amps and modern batteries exceeding 1,000 amps.
  • There are inquiries about connecting a car battery to a motor, with suggestions that the current draw depends on the motor's load, and that maximum current occurs when the motor is stalled.
  • Participants discuss the differences between brushed and brushless DC motors, noting that brushless motors require a controller and that both the motor and controller will limit voltage and current.
  • One participant expresses interest in creating a magnetic motor generator, prompting a clarification that all electric motors are inherently magnetic.
  • There is a debate about the terminology of "motor generator," with some participants questioning the compatibility of the two concepts and discussing their roles in converting electrical power.
  • Further inquiries about using neodymium or alnico magnets in the context of magnetic power generators are raised, but responses indicate confusion or dismissal of the topic.

Areas of Agreement / Disagreement

Participants express various viewpoints on the specifications and applications of car batteries and motors, with some disagreements about the terminology and feasibility of magnetic motors and generators. The discussion remains unresolved on several points, particularly regarding the construction and functionality of magnetic power generators.

Contextual Notes

There are limitations in the discussion regarding the assumptions made about motor types, the specifics of electrical connections, and the definitions of terms like "motor generator." Some participants also express uncertainty about the practical implications of their inquiries.

94yashwanth
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hey guys can anyone pls say how much current in amps does a ordinary car battery of 12v generates?? pls...
 
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Generally, the measurement used is "cold cranking amps", which is the bottom line when it comes to starting the vehicle. In the old days, that used to be somewhere around 350. I had to mount a 690 amp tractor battery in the trunk of my Roadrunner, in parallel with the standard unit, in order to start the engine in winter. Nowadays, though, you can get over 1,000 in a standard size case.
 
Danger said:
Generally, the measurement used is "cold cranking amps", which is the bottom line when it comes to starting the vehicle. In the old days, that used to be somewhere around 350. I had to mount a 690 amp tractor battery in the trunk of my Roadrunner, in parallel with the standard unit, in order to start the engine in winter. Nowadays, though, you can get over 1,000 in a standard size case.




thanx dude...and how can we connect a car battery to a motor?? and how to increase the RPM of a motor?? any idea!
 
94yashwanth said:
thanx dude...and how can we connect a car battery to a motor?? and how to increase the RPM of a motor?? any idea!

Can you elaborate one what you are trying to do exactly? It sounds like you want to pump a lot of amps through an electric motor, which is probably a very bad idea if you don't really know what you are doing.
 
94yashwanth said:
thanx dude...and how can we connect a car battery to a motor?? and how to increase the RPM of a motor?? any idea!
Assuming it's a "12 volt" (actually 12.8 volts or more if something is charging the battery at the same time) volt brushed DC motor, the current draw will be related to the load on the motor, with max current occurring on a stalled (not rotating) motor. As long as the battery can produce enough voltage and current, the limitation is on the motor side. Most motors will burn up if under too heavy a load and/or running for too long a time.

If it's a 12 volt brushless dc motor, you'll need a controller, and both the motor and controller will limit voltage and current.

Max rpm occurs under no load. Unless you run excessive voltage into a motor, like trying to run a 9 volt motor with a 12 volt source, there shouldn't be any issues with zero or light loads on the motor.
 
rcgldr said:
Assuming it's a "12 volt" (actually 12.8 volts or more if something is charging the battery at the same time) volt brushed DC motor, the current draw will be related to the load on the motor, with max current occurring on a stalled (not rotating) motor. As long as the battery can produce enough voltage and current, the limitation is on the motor side. Most motors will burn up if under too heavy a load and/or running for too long a time.

If it's a 12 volt brushless dc motor, you'll need a controller, and both the motor and controller will limit voltage and current.

Max rpm occurs under no load. Unless you run excessive voltage into a motor, like trying to run a 9 volt motor with a 12 volt source, there shouldn't be any issues with zero or light loads on the motor.


thanx dude...adn any idea how to make a magnetic motor!
 
94yashwanth said:
thanx dude...adn any idea how to make a magnetic motor!

:confused: :rolleyes:
All electric motors are magnetic. That's the only reason that they work.
 
Danger said:
:confused: :rolleyes:
All electric motors are magnetic. That's the only reason that they work.


yeah i do knw that...i wanted to know how to make a magnetic motor generator...
 
  • #10
94yashwanth said:
motor generator...
Isn't that an oxymoron?

A motor takes electricity and produces work. A generator has work acted upon it and produces electricity.

They are antipodal.
 
  • #11
DaveC426913 said:
Isn't that an oxymoron?

A motor takes electricity and produces work. A generator has work acted upon it and produces electricity.

They are antipodal.

http://en.wikipedia.org/wiki/Motor_Generator

Converts electrical power from one form to another. We have them at work where they convert regular 60 hz AC power into 400 hz power. An electrical motor gets power from the mains and uses it to turn a generator configured to produce the 400 hz power.
 
  • #12
DaveC426913 said:
Isn't that an oxymoron?

A motor takes electricity and produces work. A generator has work acted upon it and produces electricity.

They are antipodal.


ok...and i wanted to know is using neodymium magnts or alnico magnets how to make a magnetic power generator??
 
  • #13
Danger said:
:confused: :rolleyes:
All electric motors are magnetic. That's the only reason that they work.




ok...and i wanted to know is using neodymium magnts or alnico magnets how to make a magnetic power generator??
 
  • #14
I see where this is going.
IBTL.
 
  • #15
Troll.
 

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