Battery Leaks

[dlaing]

THE FOLLOWING IS LIFTED FROM THE SITE:http://www.windsun.com/Batteries/Battery_FAQ.htm#Temperature%20Effects%20on%20Batteries

 

snip

 

The Concorde (and most AGM) batteries have no charge or discharge current limits.

 

Excellent information, but the statement above seems dubious at best.

Maybe I am completely at a loss to understand what current is.

It seems to me if you apply a thousand amps your battery won't last very long.

But heck, maybe they are right.

Or maybe they mean no current limit if you obey the battery charging voltage limit???

Also, I don't understand what "battery charging voltage" is.

Is it the maximum, the optimal, or the minimal voltage that should be applied durring a charging? Or does it imply something else?

 

Also, I have searched the web high and low for information on how temperature effects using voltage as an indicator of state of charge (SOC)

I know the info must be on the web somewhere.

I suppose the voltage used for SOC would vary relative to temperature at about the same as battery charging voltage.

[docc]

Having looked at my ride record, I see the Guzzi went out once for 30 miles in the last 7 weeks. Ignoring that one ride, the voltage loss was about 1% per month and consistent with the 1-3% range per month expected.

 

Also, I'm interpreting the temperature data as saying to expact to charge at a higher voltage if it's cold. So, perhaps it was OK to run the charger at 16v in the 50 degree garage?

 

Just think . . . pretty soon we'll have our batteries charged, fork oil replaced and we can go riding and talk about tires and oil again!

[Steve G.]

I have a brand new Cafe Sport supposedly came with a new battery.

 

It's been ridden once since I took delivery at the end of December, about 80 miles, then stored for the past two months.

 

When I went to recharge the battery, I was astounded to see the battery is installed laying down! I noticed a pool of acid in the plastic tray under it. I truly dislike the whole idea. With the plates horizontal, the debris that flakes off over time will not fall to the bottom, but instead have a better chance of draining the battery and shortening its life. On top of that, the idea of dripping battery acid on the bike's innards makes me cringe.

 

Is this something I'm going have to keep on top of forever, or is the battery defective?

While these batteries in theory do not leak, Moto Guzzi engineering and R&D may enhance this possibility. I speak of course of the fact that over time, in warm weather, the seat pan tends to sag, and this causes solid contact of the seat pan upon the battery. I have a couple 1/4" grooves worn into my battery, so have glued 1/4" rubber strips onto the battery to stop this. However, this may lead to solid weight on the battery, ultimately compromizing the seal areas.

Ciao, Steve

[Ryland3210]

Excellent information, but the statement above seems dubious at best.

Maybe I am completely at a loss to understand what current is.

It seems to me if you apply a thousand amps your battery won't last very long.

But heck, maybe they are right.

Or maybe they mean no current limit if you obey the battery charging voltage limit???

Also, I don't understand what "battery charging voltage" is.

Is it the maximum, the optimal, or the minimal voltage that should be applied durring a charging? Or does it imply something else?

 

Also, I have searched the web high and low for information on how temperature effects using voltage as an indicator of state of charge (SOC)

I know the info must be on the web somewhere.

I suppose the voltage used for SOC would vary relative to temperature at about the same as battery charging voltage.

 

My understanding is as follows:

 

They do mean no limit to current if you obey the charging voltage limit. The current will not go to thousands of amps, which would destroy the battery, if the voltage is limited.

The SOC voltage varies relative to temperature at - 3mv/degrees C.

 

 

While these batteries in theory do not leak, Moto Guzzi engineering and R&D may enhance this possibility. I speak of course of the fact that over time, in warm weather, the seat pan tends to sag, and this causes solid contact of the seat pan upon the battery. I have a couple 1/4" grooves worn into my battery, so have glued 1/4" rubber strips onto the battery to stop this. However, this may lead to solid weight on the battery, ultimately compromizing the seal areas.

Ciao, Steve

 

There is an interference problem on some models. That's why I had to modify the battery bracket and carve a piece out of my seat, as I described previously.

 

 

Having looked at my ride record, I see the Guzzi went out once for 30 miles in the last 7 weeks. Ignoring that one ride, the voltage loss was about 1% per month and consistent with the 1-3% range per month expected.

 

Also, I'm interpreting the temperature data as saying to expact to charge at a higher voltage if it's cold. So, perhaps it was OK to run the charger at 16v in the 50 degree garage?

 

Just think . . . pretty soon we'll have our batteries charged, fork oil replaced and we can go riding and talk about tires and oil again!

 

 

Your battery is doing a hell of a lot better than mine. My battery, less than one year old, loses 25% of its charge in a week! It is the rate of self discharge, not the leakage in the bike. Not acceptable in my book, and this will all the precautions I took to prevent the seat from resting on the battery, getting a new factory prepared version, and doing a very careful initial charge.

 

What model battery are you using? Is it mounted under the seat horizontally? How old is it? Does the seat bear down on it?

 

I'd be very grateful for the info.

 

 

 

Excellent information, but the statement above seems dubious at best.

Maybe I am completely at a loss to understand what current is.

It seems to me if you apply a thousand amps your battery won't last very long.

But heck, maybe they are right.

Or maybe they mean no current limit if you obey the battery charging voltage limit???

Also, I don't understand what "battery charging voltage" is.

Is it the maximum, the optimal, or the minimal voltage that should be applied durring a charging? Or does it imply something else?

 

Also, I have searched the web high and low for information on how temperature effects using voltage as an indicator of state of charge (SOC)

I know the info must be on the web somewhere.

I suppose the voltage used for SOC would vary relative to temperature at about the same as battery charging voltage.

 

To clarify, that's -3mv/degree C PER CELL, or -18mv for a 12 volt battery

[Guest Gary Cheek]

Here is a reference to typical percentage of charge/temperature chartings. The numbers may vary somewhat by maker and type of battery. The older style lead acid batteries seemed to show a larger voltage swing with temperatures as I recall.

 

http://www.buchanan1.net/lead_acid.shtml

 

My seven year old OEM battery in the 2001 Sport lost no more than 10% of it's charge during the last 4 month lay-up. Stored in a non heated shed thru a Michigan winter. I credit the slight overcharge to level out cell to cell charge levels with a good part of that. Nelf discharge rates also drop with temperatures.

I ride the Cal II all winter and have no starting problems, even on the coldest days. The Cal II uses a U1 size 35 AH battery that was purchased second hand from a friend who services hospital equipment. It's first life was as an electric wheel chair battery. The Cal II has a late model Ducati alternator and a home made regulator. There are no extra loads from heated BVDs or any of the stuff the BMW type riders use so there is no need for "float charging" that bike either. I prefer to use a jacket that is inheritly warm rather than cooking an alternator to warm up some wires in a Gerbing or Widder vest.

The only time I use a supplemental charge is for the bi-annual cell leveling "overcharge". The old Sears, manual automotive charger is pressed into service for that duty. A very hand addition for manual chargers is a simple "Variac", variable output transformer. It allows for an easy adjustment of the manual charger output giving a good range of control with MANUAL chargers (only). Lab type power supplies are also handy for maual charging. Some of them have adjustable current limits along with voltage regulation. This allows for some pretty good mafement of charging parameters. Add a simple timer and you have the basics of an excellent battery maintenance system.

You can check out Variacs and DC power supplies by searching ebay using those terms for starting out.

 

The SOC voltage rises with temperature, The voltage required to charge at a given rate of current rises when the temperature is decreased.

[dlaing]

To clarify, that's -3mv/degree C PER CELL, or -18mv for a 12 volt battery

THANK YOU!

Here is the resulting chart.

Note the original chart and the red line are from a Hawker Odyssey manual

NOTE PLEASE DISREGARD THIS CHART AS IT IS WRONG

NOTE PLEASE DISREGARD THIS CHART AS IT IS WRONG

[Guest Gary Cheek]

Don't confuse CHARGING voltages and RESTING voltages at different temperatures. The RESTING voltage increases with a temperature RISE. The CHARGING voltage INCREASES with a temperature decrease.

 

Temperature: 7 degrees Fahrenheit

 

Percent Hydrometer Unloaded

charge reading voltage

100 1.242 12.49

75 1.187 12.16

50 1.137 11.86

25 1.097 11.62

0 1.077 11.50

 

Temperature: 107 degrees Fahrenheit

 

Percent Hydrometer Unloaded

charge reading voltage

100 1.275 12.69

75 1.220 12.36

50 1.170 12.06

25 1.130 11.82

0 1.110 11.70

 

(Typical lead acid battery)

[dlaing]

Here is a reference to typical percentage of charge/temperature chartings. The numbers may vary somewhat by maker and type of battery. The older style lead acid batteries seemed to show a larger voltage swing with temperatures as I recall.

http://www.buchanan1.net/lead_acid.shtml

 

Thanks Gary!

But that appears to be very different than the results I got from Ryland's numbers.

Ryland's voltage goes down with temperature and the site you provided goes up.

I think I have to re-do the chart

 

Don't confuse CHARGING voltages and RESTING voltages at different temperatures. The RESTING voltage increases with a temperature RISE. The CHARGING voltage INCREASES with a temperature decrease.

 

Temperature: 7 degrees Fahrenheit

 

Percent Hydrometer Unloaded

charge reading voltage

100 1.242 12.49

75 1.187 12.16

50 1.137 11.86

25 1.097 11.62

0 1.077 11.50

 

Temperature: 107 degrees Fahrenheit

 

Percent Hydrometer Unloaded

charge reading voltage

100 1.275 12.69

75 1.220 12.36

50 1.170 12.06

25 1.130 11.82

0 1.110 11.70

 

(Typical lead acid battery)

Thank You!

Perhaps tonight, I WILL REDO THE CHART WITH THE NUMBERS FROM THAT SITE (forcing them to correspond to higher AGM hawker numbers )

[dlaing]

Speaking of Odyssey batteries, A side note for any computer coders out there,

The story of Codysseus – Κοδυσσευς:

http://www.samag.com/documents/s=10112/sam0702c/0702c.htm

(way over my head on every level, but I am told it is hilarious )

[badmotogoozer]

I will have Isidor Buchmann (author of Battery University) in my office late this aft to discuss his presenting to our students as a regular guest lecturer.

 

Any specific questions anyone would like answered?

 

Rj

[Guest Mattress]

I will have Isidor Buchmann (author of Battery University) in my office late this aft to discuss his presenting to our students as a regular guest lecturer.

 

Any specific questions anyone would like answered?

 

Rj

 

Why does it hurt when I put my tounge across the terminals? Is my nervous system shot from worrying about what is going to break/fall off/short circuit/fail on my sport?

[Guest Gary Cheek]

Thanks Gary!

But that appears to be very different than the results I got from Ryland's numbers.

Ryland's voltage goes down with temperature and the site you provided goes up.

I think I have to re-do the chart

Thank You!

Perhaps tonight, I WILL REDO THE CHART WITH THE NUMBERS FROM THAT SITE (forcing them to correspond to higher AGM hawker numbers )

 

The voltages do vary between different types of batteries but open circuit resting voltages are generally driven down with the temperature while the charging voltage for a given charge rate are increased when temps drop. It just takes a higher voltage to force the chemical reaction at lower temperatures while higher temperatures produce a higher voltage from within the cells due to more vigorous chemical activity at higher temperatures. Charging and discharging are opposites, it follows the voltage relationships are influenced in opposite manners.

 

I cannot speak for Ryland's numbers .

 

Why does it hurt when I put my tounge across the terminals? Is my nervous system shot from worrying about what is going to break/fall off/short circuit/fail on my sport?

 

 

No, it is just the exteme extension of the tongue. Why would you worry about something about to " break/fall off/short circuit/fail " anyhow? Guzzis don't break like the other makes do.

[Ryland3210]

The voltages do vary between different types of batteries but open circuit resting voltages are generally driven down with the temperature while the charging voltage for a given charge rate are increased when temps drop. It just takes a higher voltage to force the chemical reaction at lower temperatures while higher temperatures produce a higher voltage from within the cells due to more vigorous chemical activity at higher temperatures. Charging and discharging are opposites, it follows the voltage relationships are influenced in opposite manners.

 

I cannot speak for Ryland's numbers .

No, it is just the exteme extension of the tongue. Why would you worry about something about to " break/fall off/short circuit/fail " anyhow? Guzzis don't break like the other makes do.

 

My numbers came from none other than the Battery University website! I had a recollection that there was a negative voltage temperature coefficient from looking into this years ago, so I looked it up.

 

I designed an electronic voltage regulator to replace the relay devices used back in the 60's. It worked pretty well. My '63 Olds' original battery outlasted the car, which died around 1972. It still ran great, with about 180,000 miles, but after bringing it back to Aamco for the fourth time for a replacement transmission (they gave a real lifetime guarantee back then), Aamco refused to honor it any longer, so I gave the car to the mechanic in the shop. I have no idea how much longer the battery lasted, but it was still starting the ungaraged Olds right through the winter with no problem

 

I think Gary and I are in what I call "violent agreement"! He's provided a thorough description of the interactions as I understand them.

[dlaing]

 

No, it is just the exteme extension of the tongue.

I think I now know who the dude is behind Mattress' avatar

[dlaing]

 

I think Gary and I are in what I call "violent agreement"! He's provided a thorough description of the interactions as I understand them.

So, were the conflicting posts the violent part of the agreement?

I assume you agree with him that when determining SOC, Voltage rises with and drops with temperature and that when you were answering me before, you were thinking charging voltage and not the voltage that we would look at to determine state of charge.