Jump pack cable??
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,071
Likes: 1,006
so you think that battery in the jump start pack actually supplies the amps necessary to start an engine????
all the jump pack does is supply a voltage assist, the down battery supplies the amperage. if the battery is a dud, no starter pack will kick the beast to life.
voltage is the electrical force that causes current to flow. the water hose analogy while not truly correct it does present the concept. it is the pressure that starts flow. think of a spark plug, it will only spark if the voltage is high enough.
the starter needs a certain voltage level to over come the resistance by supplying the magnetic field that pushes against the armature. once moving, the amperage carries it through.
like a manual foot. your leg pushes against the mass but once the mass is moving, its weight carries it through. need proof, ever yanked on a manual foot only to be suspended in mid air???
all the jump pack does is supply a voltage assist, the down battery supplies the amperage. if the battery is a dud, no starter pack will kick the beast to life.
voltage is the electrical force that causes current to flow. the water hose analogy while not truly correct it does present the concept. it is the pressure that starts flow. think of a spark plug, it will only spark if the voltage is high enough.
the starter needs a certain voltage level to over come the resistance by supplying the magnetic field that pushes against the armature. once moving, the amperage carries it through.
like a manual foot. your leg pushes against the mass but once the mass is moving, its weight carries it through. need proof, ever yanked on a manual foot only to be suspended in mid air???
Road Master
Joined: Nov 2019
Posts: 934
Likes: 677
From: Ohio
so you think that battery in the jump start pack actually supplies the amps necessary to start an engine????
all the jump pack does is supply a voltage assist, the down battery supplies the amperage. if the battery is a dud, no starter pack will kick the beast to life.
voltage is the electrical force that causes current to flow. the water hose analogy while not truly correct it does present the concept. it is the pressure that starts flow. think of a spark plug, it will only spark if the voltage is high enough.
the starter needs a certain voltage level to over come the resistance by supplying the magnetic field that pushes against the armature. once moving, the amperage carries it through.
like a manual foot. your leg pushes against the mass but once the mass is moving, its weight carries it through. need proof, ever yanked on a manual foot only to be suspended in mid air???
all the jump pack does is supply a voltage assist, the down battery supplies the amperage. if the battery is a dud, no starter pack will kick the beast to life.
voltage is the electrical force that causes current to flow. the water hose analogy while not truly correct it does present the concept. it is the pressure that starts flow. think of a spark plug, it will only spark if the voltage is high enough.
the starter needs a certain voltage level to over come the resistance by supplying the magnetic field that pushes against the armature. once moving, the amperage carries it through.
like a manual foot. your leg pushes against the mass but once the mass is moving, its weight carries it through. need proof, ever yanked on a manual foot only to be suspended in mid air???
Supporter
Joined: Jan 2022
Posts: 566
Likes: 472
From: Sapulpa, OKlahoma
Ive started my truck using a jump pack with the battery completely disconnected. Ive also seen a completely dead battery drain a jump pack before it could get any current to the starter.
Amps are only a measure of how many electrons are moving through a conductor (current), the starter doesnt care whether the electrons are coming from the battery, the jump pack, or a combination of both. The electrons are going to come from whichever source has the highest voltage.
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,071
Likes: 1,006
well mr. noobie
so can walmart electronics batteries.
i can start off running from a dead stop but 5 yards down i am starting to slow down
hummm now at my age it is all about "i think i can"
depending upon chemistry and other factors, an "aa" battery can achieve around 15 amps at a dead short!
when you kick in an electric motor there is an inrush current needed to over come mass but once moving, drops to running amp (also dependent upon load)
take a look at a signature of a spark plug from it we can see voltage and current relationships.
is it like a square wave???? naw
pretty much a spike and fall. high voltage, inrush of current and fall of voltage and waning of current.
if it wasn't for that relationship a 225 amp battery would pretty much fail trying to sustain a 400+ current full time.
a class "d" starting battery can supply well over 1000 amps, shoot you can even weld with one.
if you sustain inrush on the li battery it would over heat and explode or burst into flames. sometime it can do it on its own due to internal high resistance hence parked cars bursting into flames.
so can walmart electronics batteries.
i can start off running from a dead stop but 5 yards down i am starting to slow down
hummm now at my age it is all about "i think i can"
depending upon chemistry and other factors, an "aa" battery can achieve around 15 amps at a dead short!
when you kick in an electric motor there is an inrush current needed to over come mass but once moving, drops to running amp (also dependent upon load)
take a look at a signature of a spark plug from it we can see voltage and current relationships.
is it like a square wave???? naw
pretty much a spike and fall. high voltage, inrush of current and fall of voltage and waning of current.
if it wasn't for that relationship a 225 amp battery would pretty much fail trying to sustain a 400+ current full time.
a class "d" starting battery can supply well over 1000 amps, shoot you can even weld with one.
if you sustain inrush on the li battery it would over heat and explode or burst into flames. sometime it can do it on its own due to internal high resistance hence parked cars bursting into flames.
Road Master
Joined: Nov 2019
Posts: 934
Likes: 677
From: Ohio
well mr. noobie
so can walmart electronics batteries.
i can start off running from a dead stop but 5 yards down i am starting to slow down
hummm now at my age it is all about "i think i can"
depending upon chemistry and other factors, an "aa" battery can achieve around 15 amps at a dead short!
when you kick in an electric motor there is an inrush current needed to over come mass but once moving, drops to running amp (also dependent upon load)
take a look at a signature of a spark plug from it we can see voltage and current relationships.
is it like a square wave???? naw
pretty much a spike and fall. high voltage, inrush of current and fall of voltage and waning of current.
if it wasn't for that relationship a 225 amp battery would pretty much fail trying to sustain a 400+ current full time.
a class "d" starting battery can supply well over 1000 amps, shoot you can even weld with one.
if you sustain inrush on the li battery it would over heat and explode or burst into flames. sometime it can do it on its own due to internal high resistance hence parked cars bursting into flames.
so can walmart electronics batteries.
i can start off running from a dead stop but 5 yards down i am starting to slow down
hummm now at my age it is all about "i think i can"
depending upon chemistry and other factors, an "aa" battery can achieve around 15 amps at a dead short!
when you kick in an electric motor there is an inrush current needed to over come mass but once moving, drops to running amp (also dependent upon load)
take a look at a signature of a spark plug from it we can see voltage and current relationships.
is it like a square wave???? naw
pretty much a spike and fall. high voltage, inrush of current and fall of voltage and waning of current.
if it wasn't for that relationship a 225 amp battery would pretty much fail trying to sustain a 400+ current full time.
a class "d" starting battery can supply well over 1000 amps, shoot you can even weld with one.
if you sustain inrush on the li battery it would over heat and explode or burst into flames. sometime it can do it on its own due to internal high resistance hence parked cars bursting into flames.
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,071
Likes: 1,006
yep
flawed thinking on your part.
does not follow science
https://www.ufinebattery.com/blog/li...-and-amperage/
the whole purpose of an ion battery is to maintain voltage level, a big plus. before panties bunch up, yes the level will drop same as any other storage battery but they do it better.
flawed thinking on your part.
does not follow science
https://www.ufinebattery.com/blog/li...-and-amperage/
the whole purpose of an ion battery is to maintain voltage level, a big plus. before panties bunch up, yes the level will drop same as any other storage battery but they do it better.
Road Master
Joined: Nov 2019
Posts: 934
Likes: 677
From: Ohio
yep
flawed thinking on your part.
does not follow science
https://www.ufinebattery.com/blog/li...-and-amperage/
the whole purpose of an ion battery is to maintain voltage level, a big plus. before panties bunch up, yes the level will drop same as any other storage battery but they do it better.
flawed thinking on your part.
does not follow science
https://www.ufinebattery.com/blog/li...-and-amperage/
the whole purpose of an ion battery is to maintain voltage level, a big plus. before panties bunch up, yes the level will drop same as any other storage battery but they do it better.
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Club Member
Joined: Apr 2016
Posts: 11,581
Likes: 8,408
From: Inland NW
He can't.
They do work great, all of my techs now keep one on their box. The Noco and Hulkman are the favorites. I have seen them start diesels, and gas engines without a battery.
I remember when these came out, I was skeptical of their performance, but they have proven to be very handy and practical. We keep them in all of our service trucks and delivery trucks, now.
I keep a Noco in my bike with that cable posted, and I have a 2K Hulkman Alpha in my pickup that I have had to use one time, so far.
They do work great, all of my techs now keep one on their box. The Noco and Hulkman are the favorites. I have seen them start diesels, and gas engines without a battery.
I remember when these came out, I was skeptical of their performance, but they have proven to be very handy and practical. We keep them in all of our service trucks and delivery trucks, now.
I keep a Noco in my bike with that cable posted, and I have a 2K Hulkman Alpha in my pickup that I have had to use one time, so far.
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,071
Likes: 1,006
granted, a jump pack can start an engine without a battery
as brought out dead short currents.
but what i was bringing out is
IT IS THE VOLTAGE BOOST THAT DOES THE JOB
the whole thing is that the ion battery will maintain high voltage to near its depletion.
it takes diff'l to make current flow, aka, voltage.
as voltage drops internal resistance limits current.
by maintaining higher voltage less current in needed as brought out in the link.
i will concede that i jump the gun on the dud battery.
as brought out dead short currents.
but what i was bringing out is
IT IS THE VOLTAGE BOOST THAT DOES THE JOB
the whole thing is that the ion battery will maintain high voltage to near its depletion.
it takes diff'l to make current flow, aka, voltage.
as voltage drops internal resistance limits current.
by maintaining higher voltage less current in needed as brought out in the link.
i will concede that i jump the gun on the dud battery.
Last edited by bustert; Apr 7, 2025 at 10:57 AM.