Topic: Filling and charging a new battery - just how hot should the battery get ???

[greenjeans]

** UPDATE ** filled with the solution.   Now I'm letting it sit.  The battery is getting pretty warm.   I'm guessing this is usual ?
How hot can it get before I should start to worry ?

I picked up a Virago the other day (it was dang near free - couldn't say no)  I know this probably isn't the correct forum but I figure our CBs have batteries and the info could help.   Anyway, I have a battery that came with the bike.  The electrolyte/acid solution in a sealed, separate container.   The battery did not come with instructions and after searching the web I can not find a pdf of the instructions.   It is a Champion 50N18LA2.  It is several years old, but that shouldn't matter because the acid/electrolyte is still sealed up and the battery is dry... right ?   I know I'm probably over thinking this, but is it as simple as adding the solution to the battery, letting it settle for an hour or two and then charging it ?    I have a battery tender jr and a bigger sears battery charger that has more settings I can use.      Any suggestions ?     How long and what amperage should I charge the battery ?   

I usually just buy sealed batteries that are ready to go.    Help me with this battery so I can turn this virago into a set of pipes for my latest CB project.  Thanks

[onepieceatatime]

  I know I'm probably over thinking this, but is it as simple as adding the solution to the battery, letting it settle for an hour or two and then charging it ?    I have a battery tender jr and a bigger sears battery charger that has more settings I can use.      Any suggestions ?     How long and what amperage should I charge the battery ?   

This is exactly how the instructions for my new battery said to do it. After sitting for an hour, the instructions said to use a 500mA charger for 12 hours.

It also said to leave the caps loose until after charging.

[brewsky]

Most batteries I've used say to charge at 1/10 of the Amp Hour rating of the battery.

In your case its probably a 20 AH, so use 2 amp setting if available.

I have used a battery tender jr (I believe they are 1 amp) and it will work also, just take a little longer.

If your charger is automatic, just leave on charge till the green light comes on.

If not, one way to determine full charge is "open circuit steady state voltage" should be 12.7 or more. Which means 24 hours after charging and no use.

[lone*X]

2 amps on a motorcycle battery can cook off quite a bit of electrolyte.  Use the battery tender instead and let it charge at least 12 hours.  A good battery tender will also protect against overcharge and shut down when the battery is  fully charged.  Yes they get quite warm, just leave the caps loose.   It would get a lot hotter with the full battery charger, even at 2 amps.

[brewsky]

2 amps IS the recommended charge rate for that size conventional battery (20 AH) per Yuasa.

At any rate, the tender will work fine also, as long as you leave it charging till it is fully charged.

[lone*X]

Brewsky, You are correct in that the recommended Max charge rate is 1/10 of the batteries amp rating.  Greenjeans states his battery is a Champion 50N18LA2 which is an 18 amp hour battery.   2 amps is already over the max recommended charge rate.  Also considering the poor regulation qualities of the vast majority of consumer battery chargers and you could easily be in an over charge situation.  The Sears consumer grade battery chargers (assuming that is what Greenjeans has) are not float chargers, they could easily over charge a small amp battery.  IMHO, it is always better to be safe, and the battery tender is both a low amp (depending on brand 1.2 to 1.5 amp) and a float charger.  Actually, just checked and the battery tender jr. is only .75 amps which is still plenty, but also very battery friendly.   What does charging a motorcycle battery to rapidly do?

From Motorcycle Consumer News:   Battery Charging--Easy Does It

A motorcycle battery should never receive the kind of high-rate booster charge intended for a car battery, and unfortunately that always seems to be the only type of charger a service station has on hand when your bike needs help.

Inexpensive trickle charger with pigtail connector allows easy battery charging. Do not leave these charging longer than overnight without monitoring the battery.

To learn the proper maximum charging rate for your battery, look at the alphanumeric code printed across the case of the battery and you will usually find its Amp/Hour rating. If it's not obvious, check your owners manual. The proper trickle-charging rate for a motorcycle battery is one-tenth of the A/H rating for as long as 10 hours, depending on how discharged it is. Charging faster than 2.0/2.5 amps causes overheating which can warp and even melt the battery case if ignored. High-rate charging also speeds up internal corrosion, and its visible sign is sediment buildup under the cells, which if it reaches high enough, will also permanently short out the battery. Too high a charging rate can also result in a battery that does not hold a charge because too-rapid transformation of the lead sulfate may actually trap sulfate under a surface coating of rejuvenated lead, producing a battery that can test okay but fails quickly.

I might add that after 50 years on motorcycles, and several dozens of batteries later, I concur fully with the above assessment.


 

[scottly]

Does a newly filled battery require any charging at all? I seem to recall that when the fresh electrolyte interacts with the virgin lead plates, the chemical reaction is primed and ready to go? In any case, heat is murder for lead-acid batteries, and if the heat is being generated due to over-charging, STOP NOW.

[lone*X]

Dry charge batteries (what we get when the electrolyte is packaged separately) will only come up to about 75 to 80% after filling and sitting for the recommended 2 hours.   Also need to recheck the electrolyte after that 2 hours and top it off.  Plates are close together and it takes some time (and maybe a shake or two) for all the bubbles to come to the top.   For best battery life it is highly recommended that they be slow charged to full before use.

[TwoTired]

Does a newly filled battery require any charging at all?

Yes, it does. To fully activate and involve the entire plate area.  Also, you want to "sneak up" to full charge, rather than blast it with high currents.  Multistage battery tenders do this routinely, and allow the battery to fully involve all internal extremities before electrolysis starts to take the electrolyte apart.

In any case, heat is murder for lead-acid batteries, and if the heat is being generated due to over-charging, STOP NOW.

Absolutely true.
From Yuasa...
--If the battery feels hot to the touch during charging, STOP. Allow the battery to cool before charging again. Heat damages the plates, and a battery that is too hot can explode.

Cheers,

[brewsky]

Lone*x
I agree 100% with the article, and with your theory in general, there's just a slight difference in interpretation.

Note the article does not say a MAXIMUM of 1/10 th AH.......it says the proper rate IS 1/10 the AH capacity.

That's the same thing Yuasa says for their conventional batteries.

The sites I checked show that battery and it's crossover brands to be 20 amp instead of 18, however, not knowing when it was manufactured and having it's specific spec sheet, I certainly can't be sure.

I always try to use the specific instructions that come with the battery if possible, and they do differ between different manufacturers, if not, I use the 1/10 rule.