Do you beleive these stats on Battery Voltages?

Battery Voltages
Because batteries are always referred to as 12-volt (or 6V or 24V),
it is often assumed that the normal voltage is 12V. In fact a
12V lead-acid battery only producing 12.0V is either
almost flat or is delivering a large current (under a heavy load).
In fact, a healthy 12V battery, when not being charged,
should always show 12.2 - 12.8V.

Very conveniently, the relationship between a battery's state
of charge and its voltage is linear (10% per 0.10V) between about 90%
(12.70V) and 20% (12.0V). However, when a battery has been on
charge, even if its not fully charged, the voltage will be up
around 13.8V. This will slowly drop to around 13.6V over the next
few hours, but even if left overnight it shouldn't drop below
13.0V unless the battery was only partly charged or is on the way out.
But, as soon as a reasonable sized load is switched on, the voltage
drops quite quickly until it equates to the battery's actual
state of charge. Thereafter, the rate of voltage change (under
constant load) becomes linear. Thus, in practice, the voltage
of a freshly charged battery is a poor guide to its state of charge
until some of the charge has been used.

==================================================

If the part about (will slowly drop to around 13.6V over the next
few hours) is still true for small m/cycle batteries, and is not RC/Ah
specific, then I've been getting ripped of on some of the "wet' sla GS/Yuasa
batteries I've been buying..

I know, even the "agm" Chinese batts can hold these stats, but even
13.6 volt "agm" is a drag to start, whereas even a 12.6v "wet" will snap
start better.

The Chinese "agms" seem more like a "gel" battery rather than a
Starting Battery, I think an AGM with cell vent cap holes is pretty unreal
and may just be a bunch of sponge mixed with a sulphuric acid solution,
rather than a real AGM,which is much different...and Concorde pricier.

Bob

 

Bob wrote:
....

I meant a copper ground wire where all the strands had turned green.

As for de-sulphating, I was taught that you need a constant-current
charger, and even then it's not always possible. The documentation for
the small Ctek charger I use specifically says that it switches
periodically from constant-voltage to constant-current mode. I'm pretty
sure it has succeeded on three different batteries but once it took
about a week. All of those batteries were MF Yuasa's, which I believe
is a fairly high-quality brand. One of them was three years old and had
sat in a neighbour's unused bike outside from October to June so it
never got very warm. On the other hand, it couldn't save a one-year old
cheap refillable import battery that sat unused just over the winter
months, even with two weeks on that de-sulphating charger. Maybe a more
expensive constant-current charger that can give larger currents for
short periods would have worked, I don't know. Or maybe the guy I got
the battery from had filled it with tap water that was full of various
metals. Around here there is a lot of iron in the water.

 

Well, look at psus for powering car equipment, its normally a nominal 13.8v.
Also of course all cells are not equal, and some may drop a little more
than others.

Its not just lead acid though, its all batteries and a lot of the
performance has to depend on the electrode area.
Brian

 

My GT9B-4 12v/8ah holds a 13.2 for about 10 minutes, then drops to
13.0v about 1/2 hour, then so far 3 days @ 12.9v sitting on the bench...

This is a new battery from GS-Yuasa for Can $200.00 and I can't say
it's too shit hot....my last battery was a Chinese one proly with sponge
filled acid starved cells, but it held the voltages and not the CCA/RC....

So I might think that voltage is not the last word here, until I put
a load on it. There calcs for 1000cca=196rc(reserve capacity), but how do I
configure the 12X8=96watt battery to CCA...
I guess I'll keep looking for that one, but even then it's not
"proof in the pudding"....

ThanX for the nfo

Bob


|>Well, look at psus for powering car equipment, its normally a nominal 13.8v.
|>Also of course all cells are not equal, and some may drop a little more
|>than others.
|>
|>Its not just lead acid though, its all batteries and a lot of the
|>performance has to depend on the electrode area.
|>Brian

 

Maybe internal cell resistance causes a drop of 0.3 to 0.4 volts
between the terminal posts after the battery has been allowed to rest
for half an hour or more?

 

Bob, that is a pretty high quality battery and I am pretty sure from
past posts going back a year or two that the basic problem is that it
is not a very big battery and will drain in a few days under your
conditions. No amount of calculation is going to change that. Plus,
repeated full drains are not good for any lead-acid battery's longevity.
If I parked where you have to park, with the alarm on, I might
consider putting a much larger battery in that big underseat
compartment. This would involve a fair bit of thought for all the
re-wiring. Or possibly a second small battery which would require
thinking about how to charge it, maybe with some fancy electronics or
maybe with a simple switch.

(By the way, I did have a big silver scoot some years ago, but I don't
have any grey clothes. I used to see the same guy when I lived near
there. Now I'm about forty klics south and hardly ever go up there, my
only scoots now are angel blue and burgundy in colour.)

 

If you posted it it's either a LIE or you plagerized it...

 

He no doubt did a cut-and-paste of this info, but at
least this time he used a source that was correct. Per the
basic chemistry, one lead-acid cell should provide a
nominal voltage of somewhere around 2.1, so for
a six-cell-in-series battery, you should see somewhere
around 12.6V. The "13.X" volt reading that we're used
to seeing in charging situations (including what you'd
see on a voltmeter on your car dash, since presumably
the engine is running and the system is in the "charging"
condition when you'd see this) is because you have to
use a slightly higher voltage per cell to charge the thing.
But 14-15V is high; exceed about 2.4 V/cell (14.4V across
a "12V" six-cell battery, and a lead-acid cell will start
outgassing. Typically, a charger is set to deliver something
like 2.2-2.3 V/cell, or 13.2-13.8V across the battery - and
that's the highest you should ever be reading across the
battery terminals.

Bob M.

 

I stand (well, sit) corrected, or at least amended, however
please let me add that "VRLA" does not necessarily imply
a different cell chemistry (the name itself simply means
"valve-regulated lead-acid," and refers to any of the
construction types where the battery is "sealed" and will not
vent excess gas until/unless a pressure relief valve is triggered.
These are also generally classed as "acid-starved" and/or
"recombinant" types, as they (a) generally contain less acid
than a conventional design, and (b) are constructed such that
generated hydrogen and oxygen gases will recombine rather
than vent, as long as the pressure remains below the relief
valve's trip point. However, while this permits a somewhat
higher charge voltage (and therefore faster charging) to be
safely used, the cell chemstry is very often exactly the same
as in conventional types, and so the voltage of a charged
cell or battery would in those cases also be the same. So
in the case of a VRLA type, you will often see somewhat
higher charging voltages, but the same voltage as in a conventional
type when you simply check the battery voltage on its own.

In any event, we certainly agree that one should not exceed
the recommended maximum charging voltage per the
battery manufacturer's recommendations; Bad Things can
happen if you do. 15V is high for any of these types.

Bob M.

 

Mark Olson wrote:
....

Thanks for that link. It mentioned another Yuasa pub'n that I hadn't
seen before:

http://www.yuasabatteries.com/pdfs/2009_yuasa_apps_specs.pdf

Has cross-reference for some other mfrs' batteries, plus the suggested
Yuasa batteries for a lot of bikes going back for years. Come to think,
for years I've abused their batteries too, with generally better results
than I deserved.

(I don't know if there is another powersports battery company like Yuasa
in North America who are so forthcoming with their information, maybe
they are just better at knowing their market. I remember seeing a
really nice tester they made but it was a bit too much for my
pocketbook. Would have bought one of their chargers if it had been
readily available locally.)

 

Oops, pardon me, now I`m not sure if that is a Yuasa battery. I see
that the yx400 takes a Yuasa YT9B. Is it from the GS-Ztong Yee
company... maybe that is some Yuasa partnership, I don`t know. I`ve
never paid more than CAD 100 for a Yuasa vlrf, counting 12 or 13% BC
taxes and some of them were rated 12AH.

 

On Tue, 01 Dec 2009 02:13:20 -0800, Dennis Lee Bieber

|>On Sun, 29 Nov 2009 15:22:24 -0800 (PST), âÍÁ Á³Õ »Ñ·àÁ ËØÁ
|><> declaimed the following in alt.scooter:
|>
|>> >         My GT9B-4 12v/8ah holds a 13.2 for about 10 minutes, then drops to
|>> > 13.0v about 1/2 hour, then so far 3 days @ 12.9v sitting on the bench...
|>>
|>> Maybe internal cell resistance causes a drop of 0.3 to 0.4 volts
|>> between the terminal posts after the battery has been allowed to rest
|>> for half an hour or more?
|>
|> Surface charge has dissipated... I believe instructions for my
|>charger even mention turning on the headlights for a few minutes before
|>doing a voltage reading, to ensure the surface charge on the plates has
|>dissipated.

They mention the headlight use in all manuals, but the charge on the
plates is not redundant, as I have noticed in some batteries.

I think the concept of surface charge is intended here as the
difference between a quick charge, and a slow charge, which applies to a lot
all battery systems.

Why is it that the charge is much better in a slow charge, and
better in a trickle/float/maintenace charge...

Ah, hell, were gonna get all mixed up in the terminology here, but a
"big ass" charge is a just as good as trickle charge, for all the difference
intended, if you're in a motivated hurry.

It all really "boils" down to the fact that a good M/cycle, UPS,
trailer home, "spaciality" battery is costing too much as compared to
fit-all car battery,

Bob

 

Three words: "Economy of scale"

And, look, will you please stop setting your damn follow-ups to
"poster"? I can't believe it's deliberate, but it is damned annoying.

 

On Wed, 02 Dec 2009 22:58:19 -0800, Dennis Lee Bieber

|>> It all really "boils" down to the fact that a good M/cycle, UPS,
|>> trailer home, "spaciality" battery is costing too much as compared to
|>> fit-all car battery,
|>>
|> Really -- I just spent $130 for a battery for my Jeep, and it wasn't
|>even the top-line version. The current battery in the Dungbeetle cost me
|>about $50.
|>

So you have a chinese battery for the Scoot, which I assume you keep
on overnight charges as well.....parking on the streets can be a SOB with
these batteries.

|> Granted, the Jeep still had the OEM battery after 10 years, whereas
|>the Dungbeetle (which only charges when moving faster than 10MPH --
|>idling at signals rapidly drags it down to 11V) gets sulfated after a
|>year.

Usually a starting battery only lasts about 1 year here, but
constant charging can give you 2-->3 years and more if they aren't MF and
you can replenish through the vent caps.

The agms can't take as many discharges as a Wet battery, some conclude 40
discharges of the 900 cca starting lifetimes.

Those "agm" Chinese batteries are really difficult to maintain,
since they literally have to be on a charger most of the time due to the
fact that they are immobilized sulfuric acid, and the sulfur doesn't climb
the "plates" to descend upon charging when to the molten vat of the
regular/traditional cell.

I looked into one of my "agm" and saw it as some white folded foam
dry plates...added some water to charge, but that didn't help to this point.
Usually agms only have a spoonful of water in the system of white folded
foam plates.

MF batteries are pretty screwed in the world of parking on the
streets with occasional home charging situations, whereas Wet with vented
caps, can give you a few more years.

All sorts of Dicking around with batteries put you under the
"Get-A-Life" category of life.....right, just pay the man for a new
recycled of manufacturer's defect one.

Wet batts are better for deep discharges, but maybe
deep-cycle.marine types may be better, and may be what m-cycle batteries are
more like.AGMs and Gel, don't seem to fit the picture of city driving
starting batteries.

Bob

 

On Wed, 02 Dec 2009 22:58:19 -0800, Dennis Lee Bieber

|>A high charge tends to hit resistance limits when only the surface
|>of the plates is at "full" voltage, with temperature rise (heck, the low
|>charge rate on my SC8000 is technically too high for the battery in my
|>Dungbeetle -- and compound that with the fact that the charger has
|>concluded my battery is sulfated, so goes into desulfation mode for
|>90minutes before giving up -- I have to go out every 15 minutes or so to
|>bounce the front-end shaking gas bubbles off the plates; the gas blocks
|>the charging action).

My Shumacher 1200 charger goes into desulfate mode from 2-->10 hours
depending on how really bad the battery is.

It's all auto but has a lot of manual configs to dick around with.

Bob

 

I figure the only way I can tell whether a "sealed" battery is AGM,
is that AGMs don't heat up with normal charge, whereas Flooded Wet/MF/SLA
will heat up to a boil at 12.9v.

Most aftermarket batts are AGM hybrid types and the ones you get
when you bought your NEW M/Cycle had a WET Sealed/flooded/MF Battery...the
best, but did it ever cost.
So far all the batteries I get are an AGM type, and they don't
desulphate much, even with Pulse Width or 16v/2amp sessions on autocharge
systems, they can do some good, but equalizing/desulfation is not possible
in the "AGM" batteries....they need some attended 25volts/2amp to even start
decrystalizing the soft sulphation.....hard sulphation is still impossible
to reverse.

Bob


|>
|> My GT9B-4 12v/8ah holds a 13.2 for about 10 minutes, then drops to
|>13.0v about 1/2 hour, then so far 3 days @ 12.9v sitting on the bench...
|>
|> This is a new battery from GS-Yuasa for Can $200.00 and I can't say
|>it's too shit hot....my last battery was a Chinese one proly with sponge
|>filled acid starved cells, but it held the voltages and not the CCA/RC....
|>
|> So I might think that voltage is not the last word here, until I put
|>a load on it. There calcs for 1000cca=196rc(reserve capacity), but how do I
|>configure the 12X8=96watt battery to CCA...
|> I guess I'll keep looking for that one, but even then it's not
|>"proof in the pudding"....
|>
|>ThanX for the nfo
|>
|>Bob
|>
|>
|>On Sun, 29 Nov 2009 12:05:01 GMT, "Brian Gaff" <>
|>wrote:
|>
|>|>Well, look at psus for powering car equipment, its normally a nominal 13.8v.
|>|>Also of course all cells are not equal, and some may drop a little more
|>|>than others.
|>|>
|>|>Its not just lead acid though, its all batteries and a lot of the
|>|>performance has to depend on the electrode area.
|>|>Brian

 

Manufactueres would not disagree.
It's called 'surface charge' and 'pros' will lightly load a battery
for a minute or so to
drain it before they take voltage to estimate the 'state of charge' to
which you refer.

 

On Sat, 28 Nov 2009 14:20:33 -0800 (PST), ??? ??? ????? ???


|>The manufacturer's literature that comes in the box with the battery
|>tells exactly how to fill it with the supllied electrolyte and how
|>long to charge it and at what rate.
|>
They cant be regular AGM, you can't fill a real AGM, they are
hermetically sealed with no vent caps, although some Chinese brands had (do
not remove) vent caps that worked pretty good. Once you open the vent caps,
there is a cell imbalance and a great loss of power.

Real AGMs are never filled with electrolyte, but some variants ARE.
|>
|>Then the literature says to measure the resting *open circuit* voltage
|>and specifies that 12.8 volts indicates a full charge for the AGM
|>battery.

A real AGM is about 13.00volts, and the regular "immortal" 12.9v
level being acceptable.
|>
|>If the manufacturer doesn't know the right information, who on earth
|>would know?

Usually, only an auto charger or "sense-0n-demand" type charger can
be correct as to what the battery can handle. I use an Schumacher sc1200 at
2amps/AGM/ full auto modes.....mostly.

|>
|>If I can't trust the manufacturer to give me correct information, then
|>I'm at their mercy...

Some won't admit they have an AGM config, since their battery
chargers don't top-up an AGM properly so they dick around with Yuasa
fumion/polimion/yumion wordings to confuse..somebody....Ztong calls them
AGM!
GS on the other hand calls all their GT*****/GT9B-4 ALL
AGM....GT=AGM, they finally admitted that in their 2007 catalogue status.

|>
|>The last two AGM batteries I've owned lasted 8 years without problem.

That is exceptionally good for an AGM..lemme guess ....left on
charge all night every night for 8 years....that would work, except for
street parking lot parkers like me with a 8amp battery.

--
National Association of Assault Research
Soul Yamaha Majesty400 2005, Grey, Night Rider!
http://*remove*tarbitch.balder.prohosting.com/scooter.html
http://*remove*pages.istar.ca/~vampire/YamyMajesty400.jpg

Bob

 

On Tue, 1 Dec 2009 14:21:15 -0700, "Bob Myers"

|>But 14-15V is high; exceed about 2.4 V/cell (14.4V across
|>a "12V" six-cell battery, and a lead-acid cell will start

My Camera/Quantum Bantam Charger charges a [email protected] like a
12volt@15volt would be, and then floats at a sense-on-demand.

M/C Optima type AGM chargers are 14.4 absorb and 13.8 float monitor
for AGMs.

The Yamaha Shop manual has always stated to charge to 15 volts for a
maximum of 20hours, (pause for thermal runaways) and let sit to measure the
battery voltage right.....and that's even when they had a Wet VRLA in 2004..

|>outgassing. Typically, a charger is set to deliver something
|>like 2.2-2.3 V/cell, or 13.2-13.8V across the battery - and
|>that's the highest you should ever be reading across the
|>battery terminals.

13.8v is real good, but not above the AGM volt gluttony for lack of
RC (Reserve Capacity), just another volt/amp differentiation.

Bob

 

<<<<<------CORRECTION------->>>>>

|>|>But 14-15V is high; exceed about 2.4 V/cell (14.4V across
|>|>a "12V" six-cell battery, and a lead-acid cell will start
|>
|> My Camera/Quantum Bantam Charger charges a [email protected] like a
|>12volt@15volt would be, and then floats at a sense-on-demand.
|>

Well that doesn't make too much sense, does it....it should read as
follows:

|> My Camera/Quantum Bantam Charger charges a 6volt to *7.5volts* like a
|>12volt to *15volts* would be, and then floats at a sense-on-demand.

That's for a *constant charger* an *auto charger* or *
sense-on-demand* ping charges to 16-->17volts which is what is needed to
charge a 12volts battery as per instruction manuals, but the battery label
always states (trickle charge) ^12volts^ at 10% of total battery RC amps, or
(quick charge) ^12volts^ at 30%-->60% of total battery RC amps.

There you go, they say that al over the place in all sorts of
battery literature........but in professional real-time, there are a lot of
argumentative people on that, and they would never charge a *12volt* battery
to *15volts*, even though a lot of chargers out there do that, but most
absorb to *14.4v* for the last 40+ years in all sorts of configs with the
same *13.7?* float monitor charge......

But there are exceptions, and then there are malfunctioning ones,
with all sorts of battery and charger variants

M/cycle batteries are so limited on RC (Reserve Capacity), that I
think it's time for a change like Ni-mh or Li-on, but they stuck with high
voltage because they assume most motorcycles are driven very fast, and will
gain the voltage from the alternator/generator/stator quickly/ leaving us
mostly city drivers with a dead/weak battery on most occasions.

A ^scooter specific^ rather than motorsports battery like Ni-mh or
Li-on or back to Wet may work better if you park on the streets or public
parking lots.

Bob