Battery charge tests - running a battery to 0 frequently - checking re-charge times...

[mike]

On 07-05-2022 20:31 sms <scharf.steven@geemail.com> wrote:

I have two close friends that moved from England to California. After a
couple of decades in the U.S. they learned to speak proper English, but
they occasionally slipped up.

When they first moved to the U.S. there were some embarrassing/amusing
incidents, one involving trying to buy pencil erasers at Walgreen\'s, and
one involving the item used for washing pots and pans, while on a
backpacking trip.

When a person makes a mistake like that, if you dislike them, it\'s
annoying, but if you like them, it\'s cute.

On the other hand, if you prefer speed x while driving and someone zooms by
at 2 x, they\'re an idiot but someone in front of you at 1/2 x is a jerk.

 

[Bob F]

On 5/6/2022 2:53 PM, Jeff Liebermann wrote:

On Fri, 6 May 2022 10:07:35 -0700, sms <scharf.steven@geemail.com
wrote:

On 5/6/2022 7:53 AM, Jeff Liebermann wrote:
On Fri, 6 May 2022 07:57:08 -0000 (UTC), Chris <ithinkiam@gmail.com
wrote:

Interesting to see it born out in practice, but it is a known fact. Fast
charging heats up the battery and heat damages the battery, therefore fast
charging will reduce the battery life.

Nope, or at least not what I\'ve seen with my testing (and screwing
around). A few decades ago, I decided that NiCd cells would only
become warm if over charged past 100%. Well, I was off a little but
my thermocouple tests showed that up to about 75% of full charge, I
could literally charge the NiCd cell at whatever sky high rate I found
amusing. The problem was that if I missed and went over about 85% of
full charge at the ridiculous rates I was using, the cell would
generate enough gas and heat to blow the end out and generally make a
mess.

Ni-cad cells are less efficient when slow-charged (see
https://batteryuniversity.com/article/bu-407-charging-nickel-cadmium>).

\"Where does it say that on the URL you mentioned? All I find is:
To achieve a reliable voltage signature, the charge rate must be 0.5C
and higher. Slower charging produces a less defined voltage drop,
especially if the cells are mismatched in which case each cell reaches
full charge at a different time point.\"
In other words, the dip in terminal voltage that defines EOC
(end-of-charge) is less obvious for a slow charge than for a faster
charge. If the charge controller misses this dip, it could easily
overcharge the NiCd battery and ruin it. There\'s nothing in there
about \"efficiency\".

\"Fast charging improves the charge efficiency. At 1C charge rate, the
efficiency of a standard NiCd is 91 percent and the charge time is about
an hour (66 minutes at 91 percent). On a slow charger, the efficiency
drops to 71 percent, prolonging the charge time to about 14 hours at 0.1C.

During the first 70 percent of charge, the efficiency of a NiCd is close
to 100 percent. The battery absorbs almost all energy and the pack
remains cool. NiCd batteries designed for fast charging can be charged
with currents that are several times the C-rating without extensive heat
buildup. In fact, NiCd is the only battery that can be ultra-fast
charged with minimal stress. Cells made for ultra-fast charging can be
charged to 70 percent in minutes.\"

https://batteryuniversity.com/article/bu-407-charging-nickel-cadmium

 

[Carlos E.R.]

On 2022-05-07 02:39, John McGaw wrote:

On 5/6/2022 5:14 AM, Carlos E.R. wrote:
snip...
Interesting to see it born out in practice, but it is a known fact. Fast
charging heats up the battery and heat damages the battery, therefore
fast
charging will reduce the battery life.

It would be nice if when pluging the charger the phone asked whether
we want a fast or a slow charge.



Actually, the \"adaptive charging\" option seems to do that but without
asking. Place the phone on the wireless stand after the phone knows that
it is \"sleepy time\" and it will automatically restrict the charge rate
to what is needed to have 100% at the next alarm time. It has seemed to
work fine for me on my Pixel 6 Pro, anyway. Of course you have to switch
the option on in settings before it will know to do that. I\'m guessing
that this will work with plugged-in charging but I have never really
tried and I almost never used wired charging except when in the car on a
long road trip.

Yes, my phone does say it will end charging by alarm time.

--
Cheers, Carlos.

 

[Carlos E.R.]

On 2022-05-07 03:12, nospam wrote:

In article <t54ghq$vhp$1@dont-email.me>, sms
scharf.steven@geemail.com> wrote:

If someone really wants to charge as slow as possible, with a wired
charger, you can use a data blocker and the charger will be unable to
communicate with the phone and will default to the lowest charge rate,

which will be extremely slow and might even be insufficient to overcome
idle demands of the device because it will be 5V@100ma, or 1/2 watt,
assuming it works at all, since such adapters are non-compliant with
the usb spec.

a better and more practical solution is use a 5w/1a charger, which most
people have.

Actually, my night charger does so at \"1 load unit\", and does the job
just fine.

--
Cheers, Carlos.

 

[Carlos E.R.]

On 2022-05-06 19:07, sms wrote:

On 5/6/2022 7:53 AM, Jeff Liebermann wrote:
On Fri, 6 May 2022 07:57:08 -0000 (UTC), Chris <ithinkiam@gmail.com
wrote:

Interesting to see it born out in practice, but it is a known fact. Fast
charging heats up the battery and heat damages the battery, therefore
fast
charging will reduce the battery life.

Nope, or at least not what I\'ve seen with my testing (and screwing
around).  A few decades ago, I decided that NiCd cells would only
become warm if over charged past 100%.  Well, I was off a little but
my thermocouple tests showed that up to about 75% of full charge, I
could literally charge the NiCd cell at whatever sky high rate I found
amusing.  The problem was that if I missed and went over about 85% of
full charge at the ridiculous rates I was using, the cell would
generate enough gas and heat to blow the end out and generally make a
mess.

Ni-cad cells are less efficient when slow-charged (see
https://batteryuniversity.com/article/bu-407-charging-nickel-cadmium>).

NiMH cells are best charged using the \"step-differential\" method (see
https://batteryuniversity.com/article/bu-408-charging-nickel-metal-hydride>).


It seems like many people want to believe that slow-charging batteries
has some benefit in longevity and/or capacity, so you see statements
like \"it is a known fact...,\" even when the statements are really not true.

Well, I have been slow charging my previous phone during 4 years, and
battery life is almost the same as when I bought it. There was a
decrease or impact the first year or two, then none.

If the choice is only between a) \"fast charge at high-current to 100%
capacity\" versus b) slow-charge at low current to 100% capacity\" then
yes, slow charging is better, but that\'s not how modern smart phones, or
modern electric vehicles, with lithium-based batteries actually are
charged.

--
Cheers, Carlos.

 

[sms]

On 5/8/2022 4:21 AM, Carlos E.R. wrote:

On 2022-05-07 03:12, nospam wrote:
In article <t54ghq$vhp$1@dont-email.me>, sms
scharf.steven@geemail.com> wrote:

If someone really wants to charge as slow as possible, with a wired
charger, you can use a data blocker and the charger will be unable to
communicate with the phone and will default to the lowest charge rate,

which will be extremely slow and might even be insufficient to overcome
idle demands of the device because it will be 5V@100ma, or 1/2 watt,
assuming it works at all, since such adapters are non-compliant with
the usb spec.

a better and more practical solution is use a 5w/1a charger, which most
people have.

Actually, my night charger does so at \"1 load unit\", and does the job
just fine.

nospam is wrong of course™.

You can charge at the very low rate by not letting the charger see the
resistors on the data pins.

There\'s no upside to charging at 100mA, just as there is no upside to
charging at 500mA or 1A, versus higher rate charging, but not everything
anyone does is necessarily based on actual data. You still have people
doing 3000 mile oil changes on new cars, not because they are necessary,
but because it makes them feel good.

 

[nospam]

In article <t58hup$esn$1@dont-email.me>, sms
<scharf.steven@geemail.com> wrote:

You can charge at the very low rate by not letting the charger see the
resistors on the data pins.

by not seeing the resistors (or actual negotiation), the \'very low
rate\' is 100ma, as per the usb spec, which is insufficient to charge a
phone battery.

some devices will even say not charging:
<https://cdn-60c35131c1ac185aa47dd21e.closte.com//wp-content/uploads/201
8/04/iPad-Not-Charging-Message-300x136.png>

> There\'s no upside to charging at 100mA,

because it\'s too low to actually do anything.

just as there is no upside to
charging at 500mA or 1A, versus higher rate charging,

yes there is. the upside for charging at 500ma-1a versus faster rates
is longer battery life.

but not everything
anyone does is necessarily based on actual data.

you being the prime example of that.

 

[Carlos E.R.]

On 2022-05-07 22:02, Bob F wrote:

On 5/6/2022 2:53 PM, Jeff Liebermann wrote:
On Fri, 6 May 2022 10:07:35 -0700, sms <scharf.steven@geemail.com
wrote:

....

During the first 70 percent of charge, the efficiency of a NiCd is close
to 100 percent. The battery absorbs almost all energy and the pack
remains cool. NiCd batteries designed for fast charging can be charged
with currents that are several times the C-rating without extensive heat
buildup. In fact, NiCd is the only battery that can be ultra-fast
charged with minimal stress.

Lead-acid could be fast charged. They do that some times with cars on
garages. It is dangerous, the battery must be disconnected from the car
first, or the electronics can be destroyed (overvoltage). Happened to me.

Cells made for ultra-fast charging can be
charged to 70 percent in minutes.\"

https://batteryuniversity.com/article/bu-407-charging-nickel-cadmium

--
Cheers, Carlos.

 

[Carlos E.R.]

On 2022-05-08 16:20, nospam wrote:

In article <t58hup$esn$1@dont-email.me>, sms
scharf.steven@geemail.com> wrote:


You can charge at the very low rate by not letting the charger see the
resistors on the data pins.

by not seeing the resistors (or actual negotiation), the \'very low
rate\' is 100ma, as per the usb spec, which is insufficient to charge a
phone battery.

Don\'t be that absolute. When you do that, you deserve getting the
«nospam is wrong of course™» response.

Some phones may not charge at that rate, others do.

I have one such cable with just two wires, and all of my devices (with
micro-usb connectors) can charge with it, except an old Samsung Galaxy
Mini 2 phone. That cable came with a BT headphone, probably with the
purpose of forcing slow, low rate, charging.

I have a charger with eight outputs. 2 of them are \"1 load unit\", same
as an old computer. They can charge all my phones, tablets, headsets,
cameras, etc. All of those with USB connection, that is. Except one,
that old Samsung phone.

So I intentionally use those two outputs to charge my phone while I
sleep, or other devices that I\'m likely to forget I left charging.

I have been doing that to my previous phone for four years, the battery
is just fine.

some devices will even say not charging:
https://cdn-60c35131c1ac185aa47dd21e.closte.com//wp-content/uploads/201
8/04/iPad-Not-Charging-Message-300x136.png

Ah, an iPad.

....

--
Cheers, Carlos.

 

[nospam]

In article <4j9nki-1mr.ln1@Telcontar.valinor>, Carlos E.R.
<robin_listas@es.invalid> wrote:

Lead-acid could be fast charged.

it can, but also reduces the life of the battery, depending on how fast
it is.

They do that some times with cars on
garages.

they do, because they want to move onto the next customer.

> It is dangerous,

only if improperly done.

the battery must be disconnected from the car
first, or the electronics can be destroyed (overvoltage). Happened to me.

the battery doesn\'t need to be disconnected.

modern car battery chargers initially supply a constant current until
the battery voltage rises to ~14.4v (bulk charge), at which point it
switches to constant voltage to top it off (absorption charge) until
the current draw is minimal, and then switches to trickle charging (aka
float).

when the vehicle is running, the voltage is ~13.8v with a fully charged
battery (higher if it\'s not).

chargers that do not limit voltage and/or current can destroy all sorts
of things, including the battery. do not use.

 

[nospam]

In article <289nki-7dr.ln1@Telcontar.valinor>, Carlos E.R.
<robin_listas@es.invalid> wrote:

You can charge at the very low rate by not letting the charger see the
resistors on the data pins.

by not seeing the resistors (or actual negotiation), the \'very low
rate\' is 100ma, as per the usb spec, which is insufficient to charge a
phone battery.

Don\'t be that absolute. When you do that, you deserve getting the
«nospam is wrong of course» response.

the usb spec is absolute, as are other specs.

the usb spec *requires* that a device initially source 100ma, with
higher rates only after negotiation. originally, that required a
request, but that was not practical for a simple charger, which is why
resistors were added to the spec.

if you disagree, take it up with the usb consortium.

> Some phones may not charge at that rate, others do.

the rate is defined by the usb spec.

non-compliant devices do exist, however, they should be avoided. there
is no guarantee what they will do.

compliance not only guarantees expected functionality and compatibility
between manufacturers, but also a level of safety.

I have one such cable with just two wires, and all of my devices (with
micro-usb connectors) can charge with it, except an old Samsung Galaxy
Mini 2 phone. That cable came with a BT headphone, probably with the
purpose of forcing slow, low rate, charging.

any cable with only two wires is non-compliant with the usb spec, and
if it came with a bt headphone, then that too is non-compliant.

you have a lot of non-compliant devices. that\'s unfortunate.

 

[sms]

On 5/9/2022 4:07 AM, Carlos E.R. wrote:

On 2022-05-08 16:20, nospam wrote:
In article <t58hup$esn$1@dont-email.me>, sms
scharf.steven@geemail.com> wrote:


You can charge at the very low rate by not letting the charger see the
resistors on the data pins.

by not seeing the resistors (or actual negotiation), the \'very low
rate\' is 100ma, as per the usb spec, which is insufficient to charge a
phone battery.

Don\'t be that absolute. When you do that, you deserve getting the
«nospam is wrong of course™» response.

Some phones may not charge at that rate, others do.

I have one such cable with just two wires, and all of my devices (with
micro-usb connectors) can charge with it, except an old Samsung Galaxy
Mini 2 phone. That cable came with a BT headphone, probably with the
purpose of forcing slow, low rate, charging.

I have a charger with eight outputs. 2 of them are \"1 load unit\", same
as an old computer. They can charge all my phones, tablets, headsets,
cameras, etc. All of those with USB connection, that is. Except one,
that old Samsung phone.

So I intentionally use those two outputs to charge my phone while I
sleep, or other devices that I\'m likely to forget I left charging.

I have been doing that to my previous phone for four years, the battery
is just fine.

nospam is wrong of course™

You can charge a phone, albeit very slowly, at 100mA.

There\'s no good reason to do this, but someone else was concerned that
when you plug a phone into a fast charger there is no way to force it
charge at a lower rate. For an iPhone there is two ways a) turn off the
phone, b) use a power-only USB cable or a device that prevents the data
lines from being seen.

 

[Carlos E.R.]

On 2022-05-09 13:51, nospam wrote:

In article <4j9nki-1mr.ln1@Telcontar.valinor>, Carlos E.R.
robin_listas@es.invalid> wrote:


Lead-acid could be fast charged.

it can, but also reduces the life of the battery, depending on how fast
it is.

They do that some times with cars on
garages.

they do, because they want to move onto the next customer.

It is dangerous,

only if improperly done.

the battery must be disconnected from the car
first, or the electronics can be destroyed (overvoltage). Happened to me.

the battery doesn\'t need to be disconnected.

nospam, don\'t talk of things you don\'t understand

Fast charging a lead acid battery means supplying it with a high
voltage, maybe 20 or 30 volts, much more than what the battery can
absorb. If the car is not disconnected, that voltage reaches the car itself.

What you say now is trash:

modern car battery chargers initially supply a constant current until
the battery voltage rises to ~14.4v (bulk charge), at which point it
switches to constant voltage to top it off (absorption charge) until
the current draw is minimal, and then switches to trickle charging (aka
float).

when the vehicle is running, the voltage is ~13.8v with a fully charged
battery (higher if it\'s not).

chargers that do not limit voltage and/or current can destroy all sorts
of things, including the battery. do not use.

--
Cheers, Carlos.

 

[nospam]

In article <t5bedb$8fo$1@dont-email.me>, sms
<scharf.steven@geemail.com> wrote:

> You can charge a phone, albeit very slowly, at 100mA.

extremely slowly (as in days), and it needs to be powered off because
idle power consumption is higher than 100ma.

if it\'s powered on, it won\'t actually charge, which is what causes the
no charging indicator to be shown on the display. link in another post.

There\'s no good reason to do this, but someone else was concerned that
when you plug a phone into a fast charger there is no way to force it
charge at a lower rate. For an iPhone there is two ways a) turn off the
phone,

except that the phone will turn on when connected to a charger (android
partly boots, iphone fully boots) and then will charge at whatever rate
the charger supports and negotiates with the device.

b) use a power-only USB cable or a device that prevents the data
lines from being seen.

that won\'t work. see above.

the correct way to charge at a slow rate is use a 2.5w (500ma) or 5w
charger (1a).

 

[nospam]

In article <g3unki-jk.ln1@Telcontar.valinor>, Carlos E.R.
<robin_listas@es.invalid> wrote:

the battery must be disconnected from the car
first, or the electronics can be destroyed (overvoltage). Happened to me.

the battery doesn\'t need to be disconnected.

nospam, don\'t talk of things you don\'t understand

take your own advice.

i\'m *very* familiar with battery chargers for various battery
chemistries. you clearly are not.

Fast charging a lead acid battery means supplying it with a high
voltage, maybe 20 or 30 volts, much more than what the battery can
absorb. If the car is not disconnected, that voltage reaches the car itself.

that is flat out false. where did you get that bogus information?

applying 20-30v to a 12v lead acid car battery will destroy it.

fast charging is a function of the *current*, not the voltage. see
below, and the initial charge phase is constant current, while the
battery voltage rises to a particular threshold. see below for
specifics.

> What you say now is trash:

it isn\'t.

here\'s an example of a ctek car battery charger and its various phases.
other brands are similar.

<https://www.motorcycle.com/blog/wp-content/uploads/2014/02/022514-CTEK-
battery-charger-3-chart-633x360.jpg>

modern car battery chargers initially supply a constant current until
the battery voltage rises to ~14.4v (bulk charge), at which point it
switches to constant voltage to top it off (absorption charge) until
the current draw is minimal, and then switches to trickle charging (aka
float).

when the vehicle is running, the voltage is ~13.8v with a fully charged
battery (higher if it\'s not).

chargers that do not limit voltage and/or current can destroy all sorts
of things, including the battery. do not use.

 

[sms]

On 5/9/2022 10:03 AM, Carlos E.R. wrote:

<snip>

Fast charging a lead acid battery means supplying it with a high
voltage, maybe 20 or 30 volts, much more than what the battery can
absorb. If the car is not disconnected, that voltage reaches the car
itself.

I\'ve never heard of high-voltage charging of lead-acid batteries, at
least not beyond 2.5 volts per cell (14.8V for a six cell car battery).

The exception is the \"pulse chargers\" that attempt to remove sulfation
in lead-acid batteries by using high-voltage, high-frequency pulses, and
in that case it would make sense to disconnect the battery from the
vehicle prior to attempting this.

There is no conclusive proof that pulse charging has any positive
effect, only some limited empirical evidence. There are ways to remove
sulfation from non-sealed lead-acid batteries, but not with pulsed charging.

 

[nospam]

In article <t5bk64$f9c$1@dont-email.me>, sms
<scharf.steven@geemail.com> wrote:

Fast charging a lead acid battery means supplying it with a high
voltage, maybe 20 or 30 volts, much more than what the battery can
absorb. If the car is not disconnected, that voltage reaches the car
itself.

I\'ve never heard of high-voltage charging of lead-acid batteries, at
least not beyond 2.5 volts per cell (14.8V for a six cell car battery).

2.75v is the acceptable maximum.

The exception is the \"pulse chargers\" that attempt to remove sulfation
in lead-acid batteries by using high-voltage, high-frequency pulses, and
in that case it would make sense to disconnect the battery from the
vehicle prior to attempting this.

pulse chargers are nowhere near 20-30v.

for ctek, it\'s 15.8v for the initial (and mostly useless) desulfation
phase, which will not destroy a vehicle\'s electronics.

There is no conclusive proof that pulse charging has any positive
effect, only some limited empirical evidence.

true.

There are ways to remove
sulfation from non-sealed lead-acid batteries, but not with pulsed charging.

none that reliably work.

 

[Lewis]

In message <t5bedb$8fo$1@dont-email.me> sms <scharf.steven@geemail.com> wrote:

On 5/9/2022 4:07 AM, Carlos E.R. wrote:
On 2022-05-08 16:20, nospam wrote:
In article <t58hup$esn$1@dont-email.me>, sms
scharf.steven@geemail.com> wrote:


You can charge at the very low rate by not letting the charger see the
resistors on the data pins.

by not seeing the resistors (or actual negotiation), the \'very low
rate\' is 100ma, as per the usb spec, which is insufficient to charge a
phone battery.

Don\'t be that absolute. When you do that, you deserve getting the
«nospam is wrong of course™» response.

Some phones may not charge at that rate, others do.

I have one such cable with just two wires, and all of my devices (with
micro-usb connectors) can charge with it, except an old Samsung Galaxy
Mini 2 phone. That cable came with a BT headphone, probably with the
purpose of forcing slow, low rate, charging.

I have a charger with eight outputs. 2 of them are \"1 load unit\", same
as an old computer. They can charge all my phones, tablets, headsets,
cameras, etc. All of those with USB connection, that is. Except one,
that old Samsung phone.

So I intentionally use those two outputs to charge my phone while I
sleep, or other devices that I\'m likely to forget I left charging.

I have been doing that to my previous phone for four years, the battery
is just fine.

nospam is wrong of course™

You\'re ignorance is showing.

> You can charge a phone, albeit very slowly, at 100mA.

Not likely, since the phones need to be on in order to charge, and they
use more than 100mA to be on. You will not charge the phone at 100mA,
you will very slightly slow the phones discharge.

> There\'s no good reason to do this

Of course not, since it will not charge the phone.

> For an iPhone there is two ways a) turn off the phone,

No iPhone will not charge at all when off.

--
\"Are you pondering what I\'m pondering?\"
\"I think so, Brain, but nose rings are kinda passé by now.\"

 

[Peter W.]

> No iPhone will not charge at all when off.

Funny thing, my wife\'s iPhone 13, and the two before that charged just fine when off.

https://www.iphonefaq.org/archives/97310

Jimmy Neutron is proud of itself! All this BS, stupidity and absolute crap over nothing whatsoever of substance!

Peter Wieck
Melrose Park, PA

 

[ohg...@gmail.com]

On Monday, May 9, 2022 at 2:43:33 PM UTC-4, Peter W. wrote:

No iPhone will not charge at all when off.
Funny thing, my wife\'s iPhone 13, and the two before that charged just fine when off.

Yep. Not only will all phones charge when off, they often charge faster when off although not dramatically so.