On Tue, 02 Jan 2024 22:06:29 +0100, albert@cherry.(none) (albert)
wrote:

>In article <bd636389-0a66-4610-9da1-48204bfdbc0an@googlegroups.com>,
>Fred Bloggs <bloggs.fredbloggs.fred@gmail.com> wrote:
>>On Sunday, December 31, 2023 at 6:08:27 AM UTC-5, none albert wrote:
>>> In article <1151cf17-e9c1-413e...@googlegroups.com>,
>>> Fred Bloggs <bloggs.fred...@gmail.com> wrote:
>>> >On Saturday, December 30, 2023 at 3:53:48 PM UTC-5, John Larkin wrote:
>>> >> On Sat, 30 Dec 2023 12:23:53 -0800 (PST), Fred Bloggs
>>> >> <bloggs.fred...@gmail.com> wrote:
>>> >> >On Saturday, December 30, 2023 at 2:10:58?PM UTC-5, John Larkin wrote:
>>> >> >> On Sat, 30 Dec 2023 10:08:49 -0800 (PST), Fred Bloggs
>>> >> >> <bloggs.fred...@gmail.com> wrote:
>>> >> >> >On Saturday, December 30, 2023 at 8:20:26?AM UTC-5, Cursitor Doom wrote:
>>> >> >> >> These things claim to be able to charge up from a near dead 12V car
>>> >> >> >> battery in just a few moments and then provide enough power to spin a
>>> >> >> >> car over and start it. And moreover to be able to do this up to 25
>>> >> >> >> times before the stored charged runs out. So say you have a knackered
>>> >> >> >> car battery with a terminal voltage of only 9 or 10 volts, this thing
>>> >> >> >> can draw enough energy out of it to provide 14V at sufficient current
>>> >> >> >> to spin over an engine of over 400CI (that's a typically touted figure
>>> >> >> >> for a normally aspirated petrol/gas engine and about 2/3 that for a
>>> >> >> >> diesel).
>>> >> >> >> It's the energy involved that I'm struggling to get my head around
>>> >> >> >> here. How is this seemingly miraculous tranformation achieved? I've
>>> >> >> >> been wanting to get a jump starter for emergencies for some time, but
>>> >> >> >> was put off by the thought of having a bunch of lithium cells go up in
>>> >> >> >> flames on me. This would seem to eliminate that risk.
>>> >> >> >
>>> >> >> >Low battery cell voltage means low stored charge and low energy. If it lacks the energy to start the vehicle as a battery,
>>> >then no amount of transformation is going to increase the energy content.
>>> >> >> >
>>> >> >> >Put that device in the same bin as the power factor correction devices for zero electric bills and similar junk.
>>> >> >> A fully charged car battery stores megajoules. It takes kilojoules to
>>> >> >> start a car. So a 99% dead battery still has enough energy to start a
>>> >> >> car.
>>> >> >>
>>> >> >> An ohmic load, like an old incandescent lamp, can totally discharge a
>>> >> >> battery, but modern loads are electronic, nonlinear, so a modern car
>>> >> >> doesn't fully discharge a battery any time soon.
>>> >> >>
>>> >> >> Of course, the supercap charger specs are probably as bogus as most
>>> >> >> such stuff, but they seem to work.
>>> >> >>
>>> >> >> I have a lithium battery starter which I charge occasionally. I'm
>>> >> >> optimistic it won't start my car on fire.
>>> >> >
>>> >> >I'm pretty sure SAE spec is everything, including the starter, works down to 8V. If the battery won't even turn the engine over,
>>> >it's going to take forever to charge the supercapacitor.
>>> >> Sounds like 10 minutes is typical.
>>> >
>>> >That Autowit thing on Amazon says the battery has to be no less than 12V to charge it. If the battery is less, you're supposed to go
>>> >find a 12VDC somewhere.
>>> >
>>> >People wouldn't need this if they kept their cars charged with a 'battery maintainer.' They're just an unregulated 12V PV straight
>>> >into the battery, nothing else. Once they've ruined their battery with excessive discharge, it will never fully charge right again.
>>> >A maintainer prevents that. The maintainer has a lighter socket adapter which must be disconnected before you start the car.
>>> I have discharged the gel battery of my Ford Mondeo Ghia several times
>>> to approximately 5 volts. I charge with a current of mA till the battery recovers
>>> to 10 Volt than increase slowly the current. The garage advises to
>>> change the battery, but I can till start the motor with it.
>>> It is from 2000, so if an interior light is left on, or the parking
>>> lights, it is severely discharged.
>>> It makes no sense to replace the battery, I make this mistake
>>> at least once a year.
>>> Conclusion the battery is not ruined, at least not totally.
>>
>>Most chargers won't charge a battery with that low of a terminal voltage, they assume it's a shorted cell.
>
>I do not use a charger. I use a power supply with regulated voltage and a
>current limiter. In the beginning I charge with 10 mA or such.
>I only charge with a less than 1 Volt over the current battery voltage.
>

Set the power suppy to 1 amp and 13 volts and go. It usually doesn't
take many amp-hours to start a car.

tirsdag den 2. januar 2024 kl. 22.06.40 UTC+1 skrev none albert:
> In article <bd636389-0a66-4610...@googlegroups.com>,
> Fred Bloggs <bloggs.fred...@gmail.com> wrote:
> >On Sunday, December 31, 2023 at 6:08:27 AM UTC-5, none albert wrote:
> >> In article <1151cf17-e9c1-413e...@googlegroups.com>,
> >> Fred Bloggs <bloggs.fred...@gmail.com> wrote:
> >> >On Saturday, December 30, 2023 at 3:53:48 PM UTC-5, John Larkin wrote:
> >> >> On Sat, 30 Dec 2023 12:23:53 -0800 (PST), Fred Bloggs
> >> >> <bloggs.fred...@gmail.com> wrote:
> >> >> >On Saturday, December 30, 2023 at 2:10:58?PM UTC-5, John Larkin wrote:
> >> >> >> On Sat, 30 Dec 2023 10:08:49 -0800 (PST), Fred Bloggs
> >> >> >> <bloggs.fred...@gmail.com> wrote:
> >> >> >> >On Saturday, December 30, 2023 at 8:20:26?AM UTC-5, Cursitor Doom wrote:
> >> >> >> >> These things claim to be able to charge up from a near dead 12V car
> >> >> >> >> battery in just a few moments and then provide enough power to spin a
> >> >> >> >> car over and start it. And moreover to be able to do this up to 25
> >> >> >> >> times before the stored charged runs out. So say you have a knackered
> >> >> >> >> car battery with a terminal voltage of only 9 or 10 volts, this thing
> >> >> >> >> can draw enough energy out of it to provide 14V at sufficient current
> >> >> >> >> to spin over an engine of over 400CI (that's a typically touted figure
> >> >> >> >> for a normally aspirated petrol/gas engine and about 2/3 that for a
> >> >> >> >> diesel).
> >> >> >> >> It's the energy involved that I'm struggling to get my head around
> >> >> >> >> here. How is this seemingly miraculous tranformation achieved? I've
> >> >> >> >> been wanting to get a jump starter for emergencies for some time, but
> >> >> >> >> was put off by the thought of having a bunch of lithium cells go up in
> >> >> >> >> flames on me. This would seem to eliminate that risk.
> >> >> >> >
> >> >> >> >Low battery cell voltage means low stored charge and low energy.. If it lacks the energy to start the vehicle as a battery,
> >> >then no amount of transformation is going to increase the energy content.
> >> >> >> >
> >> >> >> >Put that device in the same bin as the power factor correction devices for zero electric bills and similar junk.
> >> >> >> A fully charged car battery stores megajoules. It takes kilojoules to
> >> >> >> start a car. So a 99% dead battery still has enough energy to start a
> >> >> >> car.
> >> >> >>
> >> >> >> An ohmic load, like an old incandescent lamp, can totally discharge a
> >> >> >> battery, but modern loads are electronic, nonlinear, so a modern car
> >> >> >> doesn't fully discharge a battery any time soon.
> >> >> >>
> >> >> >> Of course, the supercap charger specs are probably as bogus as most
> >> >> >> such stuff, but they seem to work.
> >> >> >>
> >> >> >> I have a lithium battery starter which I charge occasionally. I'm
> >> >> >> optimistic it won't start my car on fire.
> >> >> >
> >> >> >I'm pretty sure SAE spec is everything, including the starter, works down to 8V. If the battery won't even turn the engine over,
> >> >it's going to take forever to charge the supercapacitor.
> >> >> Sounds like 10 minutes is typical.
> >> >
> >> >That Autowit thing on Amazon says the battery has to be no less than 12V to charge it. If the battery is less, you're supposed to go
> >> >find a 12VDC somewhere.
> >> >
> >> >People wouldn't need this if they kept their cars charged with a 'battery maintainer.' They're just an unregulated 12V PV straight
> >> >into the battery, nothing else. Once they've ruined their battery with excessive discharge, it will never fully charge right again.
> >> >A maintainer prevents that. The maintainer has a lighter socket adapter which must be disconnected before you start the car.
> >> I have discharged the gel battery of my Ford Mondeo Ghia several times
> >> to approximately 5 volts. I charge with a current of mA till the battery recovers
> >> to 10 Volt than increase slowly the current. The garage advises to
> >> change the battery, but I can till start the motor with it.
> >> It is from 2000, so if an interior light is left on, or the parking
> >> lights, it is severely discharged.
> >> It makes no sense to replace the battery, I make this mistake
> >> at least once a year.
> >> Conclusion the battery is not ruined, at least not totally.
> >
> >Most chargers won't charge a battery with that low of a terminal voltage, they assume it's a shorted cell.
> I do not use a charger. I use a power supply with regulated voltage and a
> current limiter. In the beginning I charge with 10 mA or such.
> I only charge with a less than 1 Volt over the current battery voltage.

what are you charging, buttoncells ?

On Sat, 30 Dec 2023 13:20:16 +0000, Cursitor Doom wrote:

> These things claim to be able to charge up from a near dead 12V car
> battery in just a few moments and then provide enough power to spin a
> car over and start it. And moreover to be able to do this up to 25 times
> before the stored charged runs out. So say you have a knackered car
> battery with a terminal voltage of only 9 or 10 volts, this thing can
> draw enough energy out of it to provide 14V at sufficient current to
> spin over an engine of over 400CI (that's a typically touted figure for
> a normally aspirated petrol/gas engine and about 2/3 that for a diesel).
> It's the energy involved that I'm struggling to get my head around
> here. How is this seemingly miraculous tranformation achieved? I've
> been wanting to get a jump starter for emergencies for some time, but
> was put off by the thought of having a bunch of lithium cells go up in
> flames on me. This would seem to eliminate that risk.

I have had one for a few years now. I got it early in the pandemic when my Golf R would lose charge whilst not being
used. It could only tolerate ~3 weeks of non use. It has served me quite well.

On Tue, 2 Jan 2024 16:43:47 -0800 (PST), Lasse Langwadt Christensen
<langwadt@fonz.dk> wrote:

>tirsdag den 2. januar 2024 kl. 22.06.40 UTC+1 skrev none albert:
>> In article <bd636389-0a66-4610...@googlegroups.com>,
>> Fred Bloggs <bloggs.fred...@gmail.com> wrote:
>> >On Sunday, December 31, 2023 at 6:08:27?AM UTC-5, none albert wrote:
>> >> In article <1151cf17-e9c1-413e...@googlegroups.com>,
>> >> Fred Bloggs <bloggs.fred...@gmail.com> wrote:
>> >> >On Saturday, December 30, 2023 at 3:53:48?PM UTC-5, John Larkin wrote:
>> >> >> On Sat, 30 Dec 2023 12:23:53 -0800 (PST), Fred Bloggs
>> >> >> <bloggs.fred...@gmail.com> wrote:
>> >> >> >On Saturday, December 30, 2023 at 2:10:58?PM UTC-5, John Larkin wrote:
>> >> >> >> On Sat, 30 Dec 2023 10:08:49 -0800 (PST), Fred Bloggs
>> >> >> >> <bloggs.fred...@gmail.com> wrote:
>> >> >> >> >On Saturday, December 30, 2023 at 8:20:26?AM UTC-5, Cursitor Doom wrote:
>> >> >> >> >> These things claim to be able to charge up from a near dead 12V car
>> >> >> >> >> battery in just a few moments and then provide enough power to spin a
>> >> >> >> >> car over and start it. And moreover to be able to do this up to 25
>> >> >> >> >> times before the stored charged runs out. So say you have a knackered
>> >> >> >> >> car battery with a terminal voltage of only 9 or 10 volts, this thing
>> >> >> >> >> can draw enough energy out of it to provide 14V at sufficient current
>> >> >> >> >> to spin over an engine of over 400CI (that's a typically touted figure
>> >> >> >> >> for a normally aspirated petrol/gas engine and about 2/3 that for a
>> >> >> >> >> diesel).
>> >> >> >> >> It's the energy involved that I'm struggling to get my head around
>> >> >> >> >> here. How is this seemingly miraculous tranformation achieved? I've
>> >> >> >> >> been wanting to get a jump starter for emergencies for some time, but
>> >> >> >> >> was put off by the thought of having a bunch of lithium cells go up in
>> >> >> >> >> flames on me. This would seem to eliminate that risk.
>> >> >> >> >
>> >> >> >> >Low battery cell voltage means low stored charge and low energy. If it lacks the energy to start the vehicle as a battery,
>> >> >then no amount of transformation is going to increase the energy content.
>> >> >> >> >
>> >> >> >> >Put that device in the same bin as the power factor correction devices for zero electric bills and similar junk.
>> >> >> >> A fully charged car battery stores megajoules. It takes kilojoules to
>> >> >> >> start a car. So a 99% dead battery still has enough energy to start a
>> >> >> >> car.
>> >> >> >>
>> >> >> >> An ohmic load, like an old incandescent lamp, can totally discharge a
>> >> >> >> battery, but modern loads are electronic, nonlinear, so a modern car
>> >> >> >> doesn't fully discharge a battery any time soon.
>> >> >> >>
>> >> >> >> Of course, the supercap charger specs are probably as bogus as most
>> >> >> >> such stuff, but they seem to work.
>> >> >> >>
>> >> >> >> I have a lithium battery starter which I charge occasionally. I'm
>> >> >> >> optimistic it won't start my car on fire.
>> >> >> >
>> >> >> >I'm pretty sure SAE spec is everything, including the starter, works down to 8V. If the battery won't even turn the engine over,
>> >> >it's going to take forever to charge the supercapacitor.
>> >> >> Sounds like 10 minutes is typical.
>> >> >
>> >> >That Autowit thing on Amazon says the battery has to be no less than 12V to charge it. If the battery is less, you're supposed to go
>> >> >find a 12VDC somewhere.
>> >> >
>> >> >People wouldn't need this if they kept their cars charged with a 'battery maintainer.' They're just an unregulated 12V PV straight
>> >> >into the battery, nothing else. Once they've ruined their battery with excessive discharge, it will never fully charge right again.
>> >> >A maintainer prevents that. The maintainer has a lighter socket adapter which must be disconnected before you start the car.
>> >> I have discharged the gel battery of my Ford Mondeo Ghia several times
>> >> to approximately 5 volts. I charge with a current of mA till the battery recovers
>> >> to 10 Volt than increase slowly the current. The garage advises to
>> >> change the battery, but I can till start the motor with it.
>> >> It is from 2000, so if an interior light is left on, or the parking
>> >> lights, it is severely discharged.
>> >> It makes no sense to replace the battery, I make this mistake
>> >> at least once a year.
>> >> Conclusion the battery is not ruined, at least not totally.
>> >
>> >Most chargers won't charge a battery with that low of a terminal voltage, they assume it's a shorted cell.
>> I do not use a charger. I use a power supply with regulated voltage and a
>> current limiter. In the beginning I charge with 10 mA or such.
>> I only charge with a less than 1 Volt over the current battery voltage.
>
>what are you charging, buttoncells ?

50 A-h divided by 10 mA is... what?

How can you charge at 1 volt over the current voltage? Won't that end
the universe or something?

In article <004f0ecd-5107-4273-b885-f3163a9bac9an@googlegroups.com>,
Lasse Langwadt Christensen <langwadt@fonz.dk> wrote:
>tirsdag den 2. januar 2024 kl. 22.06.40 UTC+1 skrev none albert:
>> In article <bd636389-0a66-4610...@googlegroups.com>,
>> Fred Bloggs <bloggs.fred...@gmail.com> wrote:
>> >On Sunday, December 31, 2023 at 6:08:27 AM UTC-5, none albert wrote:
>> >> In article <1151cf17-e9c1-413e...@googlegroups.com>,
>> >> Fred Bloggs <bloggs.fred...@gmail.com> wrote:
>> >> >On Saturday, December 30, 2023 at 3:53:48 PM UTC-5, John Larkin wrote:
>> >> >> On Sat, 30 Dec 2023 12:23:53 -0800 (PST), Fred Bloggs
>> >> >> <bloggs.fred...@gmail.com> wrote:
>> >> >> >On Saturday, December 30, 2023 at 2:10:58?PM UTC-5, John Larkin wrote:
>> >> >> >> On Sat, 30 Dec 2023 10:08:49 -0800 (PST), Fred Bloggs
>> >> >> >> <bloggs.fred...@gmail.com> wrote:
>> >> >> >> >On Saturday, December 30, 2023 at 8:20:26?AM UTC-5, Cursitor
>Doom wrote:
>> >> >> >> >> These things claim to be able to charge up from a near
>dead 12V car
>> >> >> >> >> battery in just a few moments and then provide enough
>power to spin a
>> >> >> >> >> car over and start it. And moreover to be able to do this
>up to 25
>> >> >> >> >> times before the stored charged runs out. So say you have
>a knackered
>> >> >> >> >> car battery with a terminal voltage of only 9 or 10 volts,
>this thing
>> >> >> >> >> can draw enough energy out of it to provide 14V at
>sufficient current
>> >> >> >> >> to spin over an engine of over 400CI (that's a typically
>touted figure
>> >> >> >> >> for a normally aspirated petrol/gas engine and about 2/3
>that for a
>> >> >> >> >> diesel).
>> >> >> >> >> It's the energy involved that I'm struggling to get my
>head around
>> >> >> >> >> here. How is this seemingly miraculous tranformation
>achieved? I've
>> >> >> >> >> been wanting to get a jump starter for emergencies for
>some time, but
>> >> >> >> >> was put off by the thought of having a bunch of lithium
>cells go up in
>> >> >> >> >> flames on me. This would seem to eliminate that risk.
>> >> >> >> >
>> >> >> >> >Low battery cell voltage means low stored charge and low
>energy. If it lacks the energy to start the vehicle as a battery,
>> >> >then no amount of transformation is going to increase the energy content.
>> >> >> >> >
>> >> >> >> >Put that device in the same bin as the power factor
>correction devices for zero electric bills and similar junk.
>> >> >> >> A fully charged car battery stores megajoules. It takes
>kilojoules to
>> >> >> >> start a car. So a 99% dead battery still has enough energy to
>start a
>> >> >> >> car.
>> >> >> >>
>> >> >> >> An ohmic load, like an old incandescent lamp, can totally
>discharge a
>> >> >> >> battery, but modern loads are electronic, nonlinear, so a modern car
>> >> >> >> doesn't fully discharge a battery any time soon.
>> >> >> >>
>> >> >> >> Of course, the supercap charger specs are probably as bogus as most
>> >> >> >> such stuff, but they seem to work.
>> >> >> >>
>> >> >> >> I have a lithium battery starter which I charge occasionally. I'm
>> >> >> >> optimistic it won't start my car on fire.
>> >> >> >
>> >> >> >I'm pretty sure SAE spec is everything, including the starter,
>works down to 8V. If the battery won't even turn the engine over,
>> >> >it's going to take forever to charge the supercapacitor.
>> >> >> Sounds like 10 minutes is typical.
>> >> >
>> >> >That Autowit thing on Amazon says the battery has to be no less
>than 12V to charge it. If the battery is less, you're supposed to go
>> >> >find a 12VDC somewhere.
>> >> >
>> >> >People wouldn't need this if they kept their cars charged with a
>'battery maintainer.' They're just an unregulated 12V PV straight
>> >> >into the battery, nothing else. Once they've ruined their battery
>with excessive discharge, it will never fully charge right again.
>> >> >A maintainer prevents that. The maintainer has a lighter socket
>adapter which must be disconnected before you start the car.
>> >> I have discharged the gel battery of my Ford Mondeo Ghia several times
>> >> to approximately 5 volts. I charge with a current of mA till the
>battery recovers
>> >> to 10 Volt than increase slowly the current. The garage advises to
>> >> change the battery, but I can till start the motor with it.
>> >> It is from 2000, so if an interior light is left on, or the parking
>> >> lights, it is severely discharged.
>> >> It makes no sense to replace the battery, I make this mistake
>> >> at least once a year.
>> >> Conclusion the battery is not ruined, at least not totally.
>> >
>> >Most chargers won't charge a battery with that low of a terminal
>voltage, they assume it's a shorted cell.
>> I do not use a charger. I use a power supply with regulated voltage and a
>> current limiter. In the beginning I charge with 10 mA or such.
>> I only charge with a less than 1 Volt over the current battery voltage.
>
>what are you charging, buttoncells ?

I charge a car battery that is supposedly dead < 5V.

Groetjes Albert
--
Don't praise the day before the evening. One swallow doesn't make spring.
You must not say "hey" before you have crossed the bridge. Don't sell the
hide of the bear until you shot it. Better one bird in the hand than ten in
the air. First gain is a cat spinning. - the Wise from Antrim -

In article <cdcbpipodflrha68pqur8hlu6fnj3v88ar@4ax.com>,
john larkin <jl@650pot.com> wrote:
>On Tue, 2 Jan 2024 16:43:47 -0800 (PST), Lasse Langwadt Christensen
><langwadt@fonz.dk> wrote:
>
>>tirsdag den 2. januar 2024 kl. 22.06.40 UTC+1 skrev none albert:
>>> In article <bd636389-0a66-4610...@googlegroups.com>,
>>> Fred Bloggs <bloggs.fred...@gmail.com> wrote:
>>> >On Sunday, December 31, 2023 at 6:08:27?AM UTC-5, none albert wrote:
>>> >> In article <1151cf17-e9c1-413e...@googlegroups.com>,
>>> >> Fred Bloggs <bloggs.fred...@gmail.com> wrote:
>>> >> >On Saturday, December 30, 2023 at 3:53:48?PM UTC-5, John Larkin wrote:
>>> >> >> On Sat, 30 Dec 2023 12:23:53 -0800 (PST), Fred Bloggs
>>> >> >> <bloggs.fred...@gmail.com> wrote:
>>> >> >> >On Saturday, December 30, 2023 at 2:10:58?PM UTC-5, John
>Larkin wrote:
>>> >> >> >> On Sat, 30 Dec 2023 10:08:49 -0800 (PST), Fred Bloggs
>>> >> >> >> <bloggs.fred...@gmail.com> wrote:
>>> >> >> >> >On Saturday, December 30, 2023 at 8:20:26?AM UTC-5,
>Cursitor Doom wrote:
>>> >> >> >> >> These things claim to be able to charge up from a near
>dead 12V car
>>> >> >> >> >> battery in just a few moments and then provide enough
>power to spin a
>>> >> >> >> >> car over and start it. And moreover to be able to do this
>up to 25
>>> >> >> >> >> times before the stored charged runs out. So say you have
>a knackered
>>> >> >> >> >> car battery with a terminal voltage of only 9 or 10
>volts, this thing
>>> >> >> >> >> can draw enough energy out of it to provide 14V at
>sufficient current
>>> >> >> >> >> to spin over an engine of over 400CI (that's a typically
>touted figure
>>> >> >> >> >> for a normally aspirated petrol/gas engine and about 2/3
>that for a
>>> >> >> >> >> diesel).
>>> >> >> >> >> It's the energy involved that I'm struggling to get my
>head around
>>> >> >> >> >> here. How is this seemingly miraculous tranformation
>achieved? I've
>>> >> >> >> >> been wanting to get a jump starter for emergencies for
>some time, but
>>> >> >> >> >> was put off by the thought of having a bunch of lithium
>cells go up in
>>> >> >> >> >> flames on me. This would seem to eliminate that risk.
>>> >> >> >> >
>>> >> >> >> >Low battery cell voltage means low stored charge and low
>energy. If it lacks the energy to start the vehicle as a battery,
>>> >> >then no amount of transformation is going to increase the energy
>content.
>>> >> >> >> >
>>> >> >> >> >Put that device in the same bin as the power factor
>correction devices for zero electric bills and similar junk.
>>> >> >> >> A fully charged car battery stores megajoules. It takes
>kilojoules to
>>> >> >> >> start a car. So a 99% dead battery still has enough energy
>to start a
>>> >> >> >> car.
>>> >> >> >>
>>> >> >> >> An ohmic load, like an old incandescent lamp, can totally
>discharge a
>>> >> >> >> battery, but modern loads are electronic, nonlinear, so a
>modern car
>>> >> >> >> doesn't fully discharge a battery any time soon.
>>> >> >> >>
>>> >> >> >> Of course, the supercap charger specs are probably as bogus as most
>>> >> >> >> such stuff, but they seem to work.
>>> >> >> >>
>>> >> >> >> I have a lithium battery starter which I charge occasionally. I'm
>>> >> >> >> optimistic it won't start my car on fire.
>>> >> >> >
>>> >> >> >I'm pretty sure SAE spec is everything, including the starter,
>works down to 8V. If the battery won't even turn the engine over,
>>> >> >it's going to take forever to charge the supercapacitor.
>>> >> >> Sounds like 10 minutes is typical.
>>> >> >
>>> >> >That Autowit thing on Amazon says the battery has to be no less
>than 12V to charge it. If the battery is less, you're supposed to go
>>> >> >find a 12VDC somewhere.
>>> >> >
>>> >> >People wouldn't need this if they kept their cars charged with a
>'battery maintainer.' They're just an unregulated 12V PV straight
>>> >> >into the battery, nothing else. Once they've ruined their battery
>with excessive discharge, it will never fully charge right again.
>>> >> >A maintainer prevents that. The maintainer has a lighter socket
>adapter which must be disconnected before you start the car.
>>> >> I have discharged the gel battery of my Ford Mondeo Ghia several times
>>> >> to approximately 5 volts. I charge with a current of mA till the
>battery recovers
>>> >> to 10 Volt than increase slowly the current. The garage advises to
>>> >> change the battery, but I can till start the motor with it.
>>> >> It is from 2000, so if an interior light is left on, or the parking
>>> >> lights, it is severely discharged.
>>> >> It makes no sense to replace the battery, I make this mistake
>>> >> at least once a year.
>>> >> Conclusion the battery is not ruined, at least not totally.
>>> >
>>> >Most chargers won't charge a battery with that low of a terminal
>voltage, they assume it's a shorted cell.
>>> I do not use a charger. I use a power supply with regulated voltage and a
>>> current limiter. In the beginning I charge with 10 mA or such.
>>> I only charge with a less than 1 Volt over the current battery voltage.
>>
>>what are you charging, buttoncells ?
>
>50 A-h divided by 10 mA is... what?
>
>How can you charge at 1 volt over the current voltage? Won't that end
>the universe or something?
>
I charge 10 mA if the current voltage is 5 V. Slowly the voltage creeps
up. For example at 8 V I risk charging with 100 mA. At the end the
battery is functional, i.e. I can start the car with it.

Groetjes Albert
--
Don't praise the day before the evening. One swallow doesn't make spring.
You must not say "hey" before you have crossed the bridge. Don't sell the
hide of the bear until you shot it. Better one bird in the hand than ten in
the air. First gain is a cat spinning. - the Wise from Antrim -

On Wed, 03 Jan 2024 20:44:53 +0100, albert@cherry.(none) (albert)
wrote:

>In article <cdcbpipodflrha68pqur8hlu6fnj3v88ar@4ax.com>,
>john larkin <jl@650pot.com> wrote:
>>On Tue, 2 Jan 2024 16:43:47 -0800 (PST), Lasse Langwadt Christensen
>><langwadt@fonz.dk> wrote:
>>
>>>tirsdag den 2. januar 2024 kl. 22.06.40 UTC+1 skrev none albert:
>>>> In article <bd636389-0a66-4610...@googlegroups.com>,
>>>> Fred Bloggs <bloggs.fred...@gmail.com> wrote:
>>>> >On Sunday, December 31, 2023 at 6:08:27?AM UTC-5, none albert wrote:
>>>> >> In article <1151cf17-e9c1-413e...@googlegroups.com>,
>>>> >> Fred Bloggs <bloggs.fred...@gmail.com> wrote:
>>>> >> >On Saturday, December 30, 2023 at 3:53:48?PM UTC-5, John Larkin wrote:
>>>> >> >> On Sat, 30 Dec 2023 12:23:53 -0800 (PST), Fred Bloggs
>>>> >> >> <bloggs.fred...@gmail.com> wrote:
>>>> >> >> >On Saturday, December 30, 2023 at 2:10:58?PM UTC-5, John
>>Larkin wrote:
>>>> >> >> >> On Sat, 30 Dec 2023 10:08:49 -0800 (PST), Fred Bloggs
>>>> >> >> >> <bloggs.fred...@gmail.com> wrote:
>>>> >> >> >> >On Saturday, December 30, 2023 at 8:20:26?AM UTC-5,
>>Cursitor Doom wrote:
>>>> >> >> >> >> These things claim to be able to charge up from a near
>>dead 12V car
>>>> >> >> >> >> battery in just a few moments and then provide enough
>>power to spin a
>>>> >> >> >> >> car over and start it. And moreover to be able to do this
>>up to 25
>>>> >> >> >> >> times before the stored charged runs out. So say you have
>>a knackered
>>>> >> >> >> >> car battery with a terminal voltage of only 9 or 10
>>volts, this thing
>>>> >> >> >> >> can draw enough energy out of it to provide 14V at
>>sufficient current
>>>> >> >> >> >> to spin over an engine of over 400CI (that's a typically
>>touted figure
>>>> >> >> >> >> for a normally aspirated petrol/gas engine and about 2/3
>>that for a
>>>> >> >> >> >> diesel).
>>>> >> >> >> >> It's the energy involved that I'm struggling to get my
>>head around
>>>> >> >> >> >> here. How is this seemingly miraculous tranformation
>>achieved? I've
>>>> >> >> >> >> been wanting to get a jump starter for emergencies for
>>some time, but
>>>> >> >> >> >> was put off by the thought of having a bunch of lithium
>>cells go up in
>>>> >> >> >> >> flames on me. This would seem to eliminate that risk.
>>>> >> >> >> >
>>>> >> >> >> >Low battery cell voltage means low stored charge and low
>>energy. If it lacks the energy to start the vehicle as a battery,
>>>> >> >then no amount of transformation is going to increase the energy
>>content.
>>>> >> >> >> >
>>>> >> >> >> >Put that device in the same bin as the power factor
>>correction devices for zero electric bills and similar junk.
>>>> >> >> >> A fully charged car battery stores megajoules. It takes
>>kilojoules to
>>>> >> >> >> start a car. So a 99% dead battery still has enough energy
>>to start a
>>>> >> >> >> car.
>>>> >> >> >>
>>>> >> >> >> An ohmic load, like an old incandescent lamp, can totally
>>discharge a
>>>> >> >> >> battery, but modern loads are electronic, nonlinear, so a
>>modern car
>>>> >> >> >> doesn't fully discharge a battery any time soon.
>>>> >> >> >>
>>>> >> >> >> Of course, the supercap charger specs are probably as bogus as most
>>>> >> >> >> such stuff, but they seem to work.
>>>> >> >> >>
>>>> >> >> >> I have a lithium battery starter which I charge occasionally. I'm
>>>> >> >> >> optimistic it won't start my car on fire.
>>>> >> >> >
>>>> >> >> >I'm pretty sure SAE spec is everything, including the starter,
>>works down to 8V. If the battery won't even turn the engine over,
>>>> >> >it's going to take forever to charge the supercapacitor.
>>>> >> >> Sounds like 10 minutes is typical.
>>>> >> >
>>>> >> >That Autowit thing on Amazon says the battery has to be no less
>>than 12V to charge it. If the battery is less, you're supposed to go
>>>> >> >find a 12VDC somewhere.
>>>> >> >
>>>> >> >People wouldn't need this if they kept their cars charged with a
>>'battery maintainer.' They're just an unregulated 12V PV straight
>>>> >> >into the battery, nothing else. Once they've ruined their battery
>>with excessive discharge, it will never fully charge right again.
>>>> >> >A maintainer prevents that. The maintainer has a lighter socket
>>adapter which must be disconnected before you start the car.
>>>> >> I have discharged the gel battery of my Ford Mondeo Ghia several times
>>>> >> to approximately 5 volts. I charge with a current of mA till the
>>battery recovers
>>>> >> to 10 Volt than increase slowly the current. The garage advises to
>>>> >> change the battery, but I can till start the motor with it.
>>>> >> It is from 2000, so if an interior light is left on, or the parking
>>>> >> lights, it is severely discharged.
>>>> >> It makes no sense to replace the battery, I make this mistake
>>>> >> at least once a year.
>>>> >> Conclusion the battery is not ruined, at least not totally.
>>>> >
>>>> >Most chargers won't charge a battery with that low of a terminal
>>voltage, they assume it's a shorted cell.
>>>> I do not use a charger. I use a power supply with regulated voltage and a
>>>> current limiter. In the beginning I charge with 10 mA or such.
>>>> I only charge with a less than 1 Volt over the current battery voltage.
>>>
>>>what are you charging, buttoncells ?
>>
>>50 A-h divided by 10 mA is... what?
>>
>>How can you charge at 1 volt over the current voltage? Won't that end
>>the universe or something?
>>
>I charge 10 mA if the current voltage is 5 V. Slowly the voltage creeps
>up. For example at 8 V I risk charging with 100 mA. At the end the
>battery is functional, i.e. I can start the car with it.
>
>Groetjes Albert

It wouldn't shock me if a battery had over 10 mA of self discharge.

But why not charge at an amp or two and be on your way? Where's the
risk?