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Battery Charger

acejones

New member
My battery dealer says I should use a CTEK charger with my Odyssey batteries.
Why wouldn't my Deltran charger be just as good ? Or is he just trying to sell me a CTEK ?
 
The CTek is better. I have a Battery Tender Plus, and when I get an Odyssey battery for my bike, the BTP will be replaced with a CTek.
 
Can someone clarify some of the battery differences and what the correct charger for each one would be? Over the life of my bike so far, I went from the factory BMW "gel cell" to a Wesco (also a gel cell, I believe), to my recently installed Odyssey PC-680. I am currently using the 12V 2.5A BMW charger designed for a gel cell, which is pretty much a battery tender in disquise. (Gawd! I only wish I could get as much battery life as Bikerfish has!) As I read this post, and started poking through the Odyssey literature, I came across this "dry cell" reference:

Like many popular spiral-wound batteries, ODYSSEY batteries employ dry cell AGM technology to contain acid, allowing the battery to be installed even on its side. But the densely packed flat plates in an ODYSSEY battery avoid the ÔÇ£dead spaceÔÇØ between cylinders in a ÔÇ£six-packÔÇØ design. The result is 15% more plate surface area ÔÇö and that translates to more power!

As I understand it, and correct me if I'm wrong, the difference between these various tenders is their rate of charge, right? Am I wrong to have the current BMW gel cell charger on this new dry cell lead battery?
 
In the good old days we had flooded wet cell lead acid batteries and they all pretty much took a charge about the same. But technology now has different battery makers building batteries - wet cell, absorbed glass mat, gel cell - differently. And I actually believe that when a battery maker specifies a specific type of three-step or four-step charging curve as being optimal they know what they are saying.

Without verifying the numbers I suspect that most any 12 v charger can charge most any 12 v battery to somewhere between 80% and 90% (or maybe a little higher) of full charge. The penalty the owner pays for using less than the optimal charger for a specific battery is probably less than full charging and maybe reduced battery life.

What I pay the most attention to is the peak charging rate allowed - because charging a battery too slowly or to less than 100% does not kill a battery, but charging at too high a voltage, or at too high a current rate can overheat a battery, warp plates, cause internal shorting, and other ills. They are packing things a lot tighter in the cases now compared to hanging some flat lead plates in an acid bath.

I am not sure there are any good general rules because even batteries of the same type - AGM for example - differ in construction, internal clearances, etc.

The best thing to do is to see what the battery maker has to say, and to avoid charging at a higher voltage or current than they recommend. That might mean buying and owning a special charger. Or it might not. Less is more - more is not.

If you are the eternal cynic and believe that folks who make their livings building and selling batteries really just want to rip you off selling a battery charger they don't even make, well you could be right but I doubt it. It seems to me battery makers survive and thrive on the reputation of their batteries - not some Chinese battery charger. So when they advise a specific charging curve as supplied by a specific charger, I tend to believe them. We went 10 full rounds on this with BMW and Deltran, until Deltran finally agreed with BMW's and Exide's position about a special charging curve for their gel (not AGM) batteries.
 
Can someone clarify some of the battery differences and what the correct charger for each one would be?

Ideally, chargers for all batteries would have a switch that allows one to select the correct cut-off or end voltage.

They would also be temperature compensated (maybe some cheaper chargers are), because the end voltage depends on the temperature and that can vary by as much as 1V or a tad more from freezing to 100F.

You are safe to use the average automatic charger which cut off at 14.4V. Unfortunately, that is a bit low for some batteries. The end result is that they never reach a full charge and the result is, shorter battery life.

Don't expect a battery to last nearly as long in the hot temperatures of Arizona as compared to Alaska.

There is way too much hype when it comes to the battery chargers offered to us.
 
They said the lead acid chargers will burn out an AGM battery. My .02

http://www.odysseyfactory.com/chargers.html

Nothing in that link tells me that a lead acid charger will burn out a AGM battery.

In fact, it won't if one adheres to the .1C or C/10 rate.

These chargers, and it doesn't matter which ones we look at, all have the same method of charging:

BULK: constant current (based on your charger) till the voltage reaches cut-off.

ABSORBTION: constant voltage (at the cut-off) with the current slowly tapering off to a set rate. This stage "finish charges" the battery.

FLOAT: when the set current rate is reach in the step above, the charger reduces the voltage limit to the mid 13s.

Its as simple as that!!!
 
Well this is an interesting bit of scrambled eggs. I, at one time sold batteries, (way before AGM), so I am well aware of charging rates, etc. What has caused this aggarvation is that my Odyssey dealer sold me a CTEK that I can't get a replacement pigtail for so I can use it on another of my bikes. I can buy the standard SAE connectors all day everywhere, but that's not what CTEK uses. I really would like to "universalize" all the pigtails on all the bikes. The CTEK seems to work fine on te R1150R, but due to lack of a pigtail I can't use it om my K75, or even my Dr200.
Interestingly I also noted that my Odyssey dealer doesn't even sell Odyssey chargers. My guess is they must have too high a price point, so he sells CTEK and Deltran. That's one of the reasons I started questioning the whole "you have to use a CTEK" thing.

This is almost as good as an oil or tire thread.
 
What they are are SAE connectors; not what is on my charger. It looks as though CTEK has changed their connectors to conform with the world. Mine is, I guess, an older charger.
 
What they are are SAE connectors; not what is on my charger. It looks as though CTEK has changed their connectors to conform with the world. Mine is, I guess, an older charger.

Why not just install a couple of Molex connectors in place of what you have. I also used gold plated pins.

I did on my Optimate III...actually, all four of them.

You can get everything from Mouser where there are no order minimums.
 
Thanks for the link. I'll check it out.

Part numbers, if you are interested...

Mouser: 538-19-09-1029, 2 circuit receptacle,
Mouser: 538-19-09-2029, 2 circuit plug,
Mouser: 538-02-09-1104, female contact, tin, 14-20 ga.
Mouser: 538-02-09-2103, male contact, tin, 14-20 ga.
 
Batteries & chargers

Most new motorcycles now have Absorbed Glass Mat (AGM) Lead acid batteries fitted. Odyssey batteries are also AGM with the difference being they are made of pure virgin lead as opposed to recycled or lead & other material (typically calcium) combo. The best thing about AGM is the power it delivers, it greatly exceeds that of std filler cap and not having to top off the battery ever again. The biggest weakness of AGM is that if left to slowly discharge as is typical on any motorcycle with a system that continues to draw power (can BUS, alarm, immobilizer etc.) it will quickly 'die' on you (i.e. become sulfated) and then a std charger will not recharge it. An automatic charger with the correct maintenance / float voltage (typically 13,5 to 13,8V for AGM) is the best to optimize power and extend life. Chargers designed for std filler cap batteries with maintenance level set at 13,2 to 13,4 will under charge an AGM battery -> result is a shortened life. So, for guys with good memories / habits any charger that maintains at around 13,5V to 13,8V can work. For the others, who sometimes forget to hook up the charger, buy one that can bring that battery back to life (desulfate), such as OptiMate. To bring back an Odessey battery also requires high current, at least 5A. Some chargers cycle maintain, meaning it allows the voltage to drop off below certain level before it charges again with it's std charge mode (up to 14,4-14,7V). CTEK's maintenance mode is like this. CTEK calls this pulse charging, but it is simply that if the battery is fully charged and it returns to charge mode 9after dropping below 12,9V) it could go back to 'no charge' mode so quick that it appears to be a pulse. In winter the cycles will increase as the battery 'rest' voltage reduces faster at low temperatures. It may be a good idea to sometimes disconnect a cyclic charger for a few days at a time to prevent overcharging.
 
Some chargers cycle maintain, meaning it allows the voltage to drop off below certain level before it charges again with it's std charge mode (up to 14,4-14,7V). CTEK's maintenance mode is like this.

The CTEK US 800 which is aimed at motorcycles does not, but the CTEK US MULTI 3300 does have an AGM/cold weather mode.

Check CTEK's online manuals if you want more details.
 
Unpopular opinion

Paul's post was well thought out and full of good information. MartinRSA's too.

Battery chemistry is way more complicated now, than it was 30 years ago when I first had to deal with dead ones. It's going to get more like that as new, more critical technology, deals with energy storage.

If you want your energy storage device to perform at it's best then you need to adhere to the manufacturers requirements. If you're tired of all that and have some sort of lead-acid battery, then screw it. Charge it with whatever you've got and replace it when it dies. You probably can't meet some of the requirements anyway.

I'll start being careful when I have Xenon crystal lattice Xbatts in my bike. they're pretty cool. 2 AAA cells will start the bike at -40 and actually run it 20 miles without other fuel in an emergency(lights off).

'til then, beat 'em up and don't worry.

:D
 
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