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new battery initial charging question

f14rio

New member
the battery says, "1.5 amps @ 5-10 hrs or 6.0 amps @ 1.0 hour"

the charger I have says, "750 milamps @ 12vdc"

so the charger only squirts 1/2 the amps the battery says it wants.

can't I just leave it connected longer to do the initial charge or is less than 1.5 amps a bad thing?
 
It has been a long time since I took that class

But, if I remember iff 1.5 amps = 5-10 hours then .75 amps =10 to 20. But heck things could have changed in 40 years ;-))
 
It depends on the battery - and its chemistry. Some batteries - Odyssey comes to mind - require a higher amperage initial charge than some other batteries. The rule of thumb generally is amps at 10% of the amp hour rating of the battery. So a 20 amp hour battery wants 2 amps and they warn about over heating the battery.

But, (Odyssey for example) wants an initial charge rate of 6 amps which is about 25% of the amp hour rating.

But for most VRLA (AGM or Gel) batteries that initial high amperage charge is not needed so your math is correct. I would use an automatic charger that goes into float mode when the battery is fully charged and just plug it in for a day - say 24 hours. I have a few different models (BT Junior, BMW, and Schumacher) and they all show a red light when charging and a green light when fully charged.

Just plug it in till the light goes to green (or whatever) and consider it good.
 
Technically its an AGM battery which is a type of VRLA (Valve Regulated Lead Acid) battery. You add acid to an AGM battery ONCE then seal it. If it were a "wet" battery it would not be sealed and you'd need to top it off with water once in a while.

Your charger will NOT harm the battery. The instructions are for those who need to use the battery NOW (and for those with stupid chargers that need to know when to turn the charger off). I assume you are at home and have time. Put in on your smart charger and keep it there until the charger says all is fully charged. Then mount the battery in the bike.

I've been with riders who in order to get back on the road in a reasonable amount of time didn't bother putting the battery on an external charger. Wasn't one available at the side of the road. We bought the battery, added the electrolyte, waited an hour over lunch, then started the bike and finished our trip. Yeah, we knew that this was not the best thing for future battery life but the goal was to get home, not to have a 5 year replacement battery for the bike. (We put the battery you pictured in a bike that called for something a bit bigger).
 
There is another procedure with these batteries that you didn't mention so I'll bring it up here. Once the acid pack is empty you leave it sit prior to charging the battery. As per Yuasa you would do the following:

1) For batteries 3 - 12 amp hour you let the battery sit for at least 30 minutes once the acid pack is empty.
2) For batteries greater than 12 amp hour allow the battery to stand at a minimum of 1 hour.

The act of letting it sit allows the electrolyte to permeate into the plate for optimum performance.

Newly activated sealed batteries require an initial charge. After filling the battery place the cap strip loosely over the filling holes. Charge the battery at the recommended rate and then fully seat the cap strip. It is at this point you can install the battery.

You will find almost no one performs the above steps because no one reads the directions and this includes dealers, independents and customers.

As for the term "optimum performance" I assume it means battery life span. I just offer the customer to do the above free of charge. Most don't want to return to the store just to pick up the battery so I'm not sure how many actually follow through on the procedure. If you have the time to follow the instructions I would do so.
 
checked instructions

did not say that in the instructions I have but it does sound like a good idea...

http://farm9.staticflickr.com/8122/8706133239_79b4398679_b.jpg


also, the green light came on in about 5 hours with the 750 mil amp charger. I hope that doesn't mean a bad thing...we'll see. :dunno

i'm coming up with 3.75 amp hours at that rate .... its a 12.6 6amp hour battery.
 
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Putting the electrolyte into the battery started you off with some amount of a charge (assuming you waited the apropriate amount of time).

How much of a charge? :dunno Enough charge to start a bike! Just don't expect to get maximum life or power out of a battery abused that way. On the other hand it will get you home if that is your need. For that kind of battery abuse I recommend cheap wal-mart batteries :laugh
 
Putting the electrolyte into the battery started you off with some amount of a charge (assuming you waited the apropriate amount of time).

How much of a charge? :dunno Enough charge to start a bike! Just don't expect to get maximum life or power out of a battery abused that way. On the other hand it will get you home if that is your need. For that kind of battery abuse I recommend cheap wal-mart batteries :laugh

Actually, filling up the battery and immediately putting it in the bike will start the bike almost 100% of the time. I've seen this repeatedly. I do think you'll end up with maximum available power once the bike has charged the battery but I've never tested that theory. I assume the real issue here is the battery life span which presumably is shortened. It's so difficult to tell because there is no consistent usage of the motorcycle. If you use your bike like most people use a car I do think an approximate 5-year life span will apply although I have had some people tell me their battery lasted 6 years. But you never know if the battery truly lasted 6 years or that's what the owner thinks it lasted.

At the end of the day once you hit the 4 or 5 year mark your battery is on borrowed time for most people.
 
thanks for the good inputs, gents

still concerned about short battery life. (this is the third on my 2010 r12r). checked dc resistance from the disconnected 12vdc battery lead to ground. (about 100k ohms, fluctuating).

I usually leave it installed in the bike in the unheated garage with a smart charger over the winter (new york). this year i'll put it in the basement on the charger.
 
still concerned about short battery life. (this is the third on my 2010 r12r).

Three batteries in three years? Either the batteries are of extremely low quality, your charging system is not up to spec, or you are not maintaining them.

The most valuable item on a motorcycle instead of the usual bling installed, is a voltmeter that indicates voltage using digits, not some meaningless LEDs. There is a thread on this forum on the latter....what a piece of garbage. I can only hope it isn't advertised in the ON.

In battery maintainer float mode...
015%20-%20Datel%20Meter%20-%20Mounted%202-M.jpg


When I am riding, it indicates actual battery voltage...14.2V.


checked dc resistance from the disconnected 12vdc battery lead to ground. (about 100k ohms, fluctuating).

That is of little use.

You want to measure the negative battery lead (disconnect it). It should be less than 1 milliohm (0.001 ohm) which you can only measure with an upper end 4-wire meter.
 

I wonder if that is actually an AGM battery.

Where are the individual valves located. I remember filling one just like it. There are no valves in the strip that is pressed into the top of the battery.

Edited to add: the YUASA chart indicates that it is a VRLA battery.

A note on these types of batteries. They do not take overcharging and ripple during charging very well. Personally, I stay clear of them when given the choice.
 
I'm curious as to which brand of AGM battery that you have to add acid to.

All the ones I've come across are filled and sealed by the manufacturer.

I have purchased several AGM batteries that came shipped with a battery, a container of acid, and a top to put on to seal the battery after I added the acid. Some of these had rather obscure names and parentage such as Everstart and Universal and UPG, but one was a Yuasa too.
 
thanks for the help, GL

I have this installed (indicates 12.9 vdc w/ motor off),

http://farm9.staticflickr.com/8115/8711123012_56955b8041_c.jpg

it also measures voltage drop during start and estimates remaining battery life. after installing the new battery and leaving it on a charger all night and a 1.0 hour ride, it reads 60 percent. it updated during starting load and can be reset to 100 percent by inturupting the 12 vdc power source.

(not good, I don't think :( )

http://farm9.staticflickr.com/8258/8711122614_9f2eb87b7f_c.jpg

the indicated voltage with the engine running is about 13.4
 

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I'm curious as to which brand of AGM battery that you have to add acid to.

All the ones I've come across are filled and sealed by the manufacturer.

By the manufacturer? Perhaps by the battery vendor. At least for motorcycle batteries. Yuasa MF (maintenance free) sealed VRLA batteries require "activation". That includes the YTX line which use an Absorbed Glass Matt separator. See page 26 of the Yuasa tech manual. http://www.yuasabatteries.com/pdfs/TechManual_2009.pdf

Yuasa is not the only manufacturer who does not pre-fill their battery. Keeping the batteries dry until put into service increases their shelf life. Some vendors pre-fill the battery before they ship it to you.
 
By the manufacturer? Perhaps by the battery vendor. At least for motorcycle batteries. Yuasa MF (maintenance free) sealed VRLA batteries require "activation". That includes the YTX line which use an Absorbed Glass Matt separator. See page 26 of the Yuasa tech manual. http://www.yuasabatteries.com/pdfs/TechManual_2009.pdf

Yuasa is not the only manufacturer who does not pre-fill their battery. Keeping the batteries dry until put into service increases their shelf life. Some vendors pre-fill the battery before they ship it to you.

The procedure spelled out in that Yuasa manual is essentially the same as I've found for the last four or five AGM batteries I've bought.
 
I have purchased several AGM batteries that came shipped with a battery, a container of acid, and a top to put on to seal the battery after I added the acid.

I noticed that after going to the YUASA site. They state the YTX14-BS is an AGM.

The question remains, where is the valve if this is a Valve Regulated Lead Acid (VRLA) battery?

On the subject of VRLA batteries...many people think AGM and GEL batteries are "sealed". Sure, most can be laid on their side, but they are not sealed; no battery that I know of is "sealed".

The AGMs that I work with, the 6T group for tanks, etc. are pre-filled and sealed. Each cap is valve vented.
 
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