Bohan
New member
Thank you Alex for sharing your vast knowledge on this thread. I've learned quite a bit.
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Battery Charger
- Thread starter acejones
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- battery charger
Thank you Alex for sharing your vast knowledge on this thread. I've learned quite a bit.
The first one is easy.
If a customer gets bad service life from the OE batt in their uber expensive m/c, and the OEM replacement is $150, and the m/c factory charger/maintainer that they "should have been using" is $150 but looks just like a $40 BT, then they'll probably look elsewhere. Figuring the "best" you can get is a 680 for $130, why not?
I'll take a stab @ the second one.
I know the bike's alternator will have way more than 6A surplus to recharge the batt. But from Odds. battery charger curve (in their app. manual), the batt. will take all the current available in the bulk charge phase (under 80% SOC) until the charge potential is up to 14.7V (@ 25*C), then the charger holds (regulates) this 14.7V while the absorption current tapers down to some low level. I don't know if the bike's alternator will regulate @ 14.7V (w/ lights, ign., and injectors running), so if not, a partially discharged (<80% SOC?) may not get the chance (time) to be fully recharged to 100% SOC (12.84 VOC).
But I'm just guessing.
globalrider
Alps Adventurer
The charging systems in our bikes do not have a "bulk mode" where the current is limited (other than the 50A limit of the alternator).
The oilhead voltage regulator, at least mine, limits to 14.2V max. I have never seen it exceed that.
The charge current to the battery will be based on the state of charge of the battery. That is why the current in the "absorbtion mode" tapers off as the battery reaches the voltage set by the charger...usually 14.2 to 14.4V.
So if anyone thinks their Odyssey battery is being charged at the minimum required 6A that Odyssey recommends...sorry, but it ain't happening on their motorcycle while in use.
If I get around to it, I'd like to get to the bottom of their "minimum charge rate" recommendation/requirement. My guess is its more advertizing than anything...people like batteries that can be charged in no time. In our case, that is of insignificant importance; on a yacht where batteries are deep cycled, its nice to be able to charge them quickly as a matter of convenience.
globalrider
Alps Adventurer
The Odyssey chargers look like re-branded Schumacher chargers, whoever makes them.
These battery charger manufacturers/resellers are very sly. Neither the Odyssey or Schumacher, Battery Tender sites provide any real specifications unless you call length, width, height and weight...specifications.
We tested two Schumacher chargers at work. I'd buy one if I needed a paperweight.
kobukan
Registered
Isn't the 6A only recommended by Odyssey for batteries that are discharged - not necessary under normal operating conditions?
Batteries are not my forte, but I'm learning and I appreciate reading all the info from you guys that obviously know a great deal more about the subject than I do. TIA
globalrider
Alps Adventurer
I sent them an e-mail requesting an explanation.
I think its more of an eye-catcher for sales...the charge-our-batteries-faster-than-any-other-battery type of thing. Not important to me unless I owned a yacht.
All the info is available on the web, but since I've been working with batteries and chargers at work for over a year, I've come across a lot of information that I have bookmarked and saved.
I don't know if anyone on here is a battery expert...I hated chemistry in school (I'm a math and physics type). Maybe someone could explain why AGM batteries dislike "ripple voltage" while charging; what does it have an effect on?
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globalrider
Alps Adventurer
In that case, I doubt the battery is ever fully charged.
Bohan
New member
Please share their response with us, Alex. I still don't understand Odyssey's rationale to support their 6A minimum requirement/recommendation other than charging speed; but again, my knowledge on the subject is very limited.
I think I could have gotten away with a CTEK 3300 and benefitted from its portability...oh, well.
globalrider
Alps Adventurer
Odyssey's reason for minimum charge rate battery chargers - their response...
So for our applications, it does not apply.
So for our applications, it does not apply.
G
GREGFUESS
Guest
What the heck does that mean in plain English? 
globalrider
Alps Adventurer
What the heck does that mean in plain English?
If their batteries are deep cycled where the depth of discharge is greater than 50%, then their minimum charge rate applies.
Automotive and motorcycle batteries do not undergo those conditions. If they are down more than a few percent, its because someone left them parked for longer periods of time without connecting a charger/maintainer or they left a high current draw device on such as headlights.
So what they are saying, you do not need to use a minimum 6A charger for your PC680 battery during normal use...at least not the way we are using them.
G
GREGFUESS
Guest
Thanks Alex. Sounds like my BTJr. is good enough for keeping my battery in good order.
globalrider
Alps Adventurer
As long as it limits at 14.7V.
I'd be concerned that the battery might not be fully charged which is why I'd like some control of the charging algorithm...say keep it at 14.7V till the current tapers off to near nothing before it transitions over to maintenance mode. Chargers usually set that point at 10% of the rated charger current, and in case it does not reach that, it times out after a few hours.
jstrube
John.
I have a TW200 that I ride very little. I took it with me to Bonneville Speed Week, then put it on the BT-jr when I got home. Went to go ride it a while ago & found 0V. Seems the battery is very low on water & checking with a DVM, had no charge at all. I'm going to try to add water & bring it back, but wouldn't its current condition be the result of an overcharge boiling all of the water out?
globalrider
Alps Adventurer
A flooded lead acid battery can dry out (very slowly) just being exposed to hot temperatures.
But battery overcharging due to an incorrectly regulating voltage regulator or one that has failed will certainly do it. How fast will depend on the voltage.
Top up the battery and place it on a slow charge at less than 1A. Monitor the battery voltage; hopefully it will make it to 14.4V.
Once you get your TW200 started, check the voltage across the battery when it is running at a few thousand RPM. With a fully charged and healthy battery in the TW200, you should see 14.2 to 14.4V.
The trouble is, although you may have a functioning voltage regulator at 27C, it probably overcharges the battery during your hot CA summers.
pglaves
#13338
We have a TW200 and Kaw KL250 Sherpa. Both have tiny wet batteries. I don't keep the maintainer chargers on these bikes for long periods of time. I keep the chargers plugged in to a switched outlet and give them a few- hour shot every couple of weeks or so. Turn the switch on and come back in a few hours - charger lights are green so I shut them off.
In the old days with a dumb charger the bikes all got 24 hours at 2 amps once a month unless ridden in the meantime.
In the old days with a dumb charger the bikes all got 24 hours at 2 amps once a month unless ridden in the meantime.
kobukan
Registered
What about Odyssey's claim that most chargers will not work because their charging voltage during the float stage is too low?
