trickle charger evaporates battery

[mason79]

i got the deltran teeny battery tender, it kept me going for a while, ( the bike starts after sitting for weeks)

today i wanted to ride, but would not start and when i took the battery out it was dry, is this suppose to happen?

if so i might as well, take it out everytime,

is the battery toast? should i even bother to fill it up with distilled water, or is it wasting my time?

help and comments?

[3Phase]

How dry was "dry"?

Always wear gloves and a face shield or safety glasses when working with batteries.

If the water is below the level of the top of the plates they may have overheated, burned and warped. If the level isn't too low then slowly add distilled water to the low level mark and recharge the battery with a 1 or 2 amp charger.

Look through the side of the case as the battery is charging. Add more water if necessary but do not try to remove it. If the battery was just mildly baked and undercharged the water level will rise. Battery cells that bubble a lot and lose water are shorted cells and the battery is toast. Watch the water over time.

Check the voltage and use a hydrometer to check the specific gravity to determine when and if the battery is fully charged.

Dan's Motorcycle Repair Web Page suggests a specific gravity of 1.26 to 1.28 and has links to some PDF files and a ZIP file about batteries.

Be careful! Always wear gloves and a face shield or safety glasses when working with batteries.


Regards,

Scott

[Larrym]

Battery tenders are definitely not supposed to boil out the electolyte. Generally these "tenders" are not battery chargers and don't put out the voltage/current needed to bring a battery up to full charge status. Instead they put out no more than 1/2 an amp and just keep the battery at the proper "floating" voltage. But to do this properly the battery itself has to have the right resistance and voltage level to begin with. If anything is off either in the tender or the battery then what happened to you will occur.

Some people have good luck with these tender thingies. I have always found that either they do what happened to you or found that even though the battery shows good "voltage", it fails under the load of starting the bike.

can only add water to a battery a limited number of times before the electrolyte is diluted to the point where it just won't do its job. I think of it like having the waitress freshen up my coffee but instead of real Java, she pours in distilled water. Not what I need to wake up in the morning. Bet you a cup of jo' that if you do fill the battery back up with water and charge it, it will not take nor keep a charge. Kinda important in a bike that needs an electric start, eh?

I have put electolyte back in batteries that were way below the normal level and had good results. Never got one back from the dead after it was bone dry though...

[oldyam80sg]

I have used Battery Tenders for years and have never had a problem with them.They will tell you to make sure that you add distilled water to them to top the battery off before charging.If you did not then i guess that the battery will be dry when you remove it,but i think because it maintains the charge only, it would never get to the point of drying out.Unless you didn't check the level beforehand.

[mason79]

i dispise checking the level but i do, and some cells would never charge up,
( older battery and was weak) maybe to 3 floating balls at the max ( cheapy ball floating hydrometer)

but to see it bone dry was a suprise as one of you mentioned it should not "boil it"

it does boil when i put it on a bigger charger, and even over days of charging it would never lift 4 balls

i ordered an agm bsattery on ebay http://stores.ebay.com/Gruber-Power-Services

for around 66 $ delivered, how do i trickle charge that now?

[oseaghdha]

If a battery goes dry, its done.
The plates get coated with lead sulfate and wont work right.
You can refill it and get a crappy charge on it, but it will fail relatively quickly.

[boyat68]

mason:

I quote from the http://www.windsun.com/Batteries/Battery_FAQ.htm "Nearly all AGM batteries are "recombinant" - what that means is that the Oxygen and Hydrogen recombine INSIDE the battery. These use gas phase transfer of oxygen to the negative plates to recombine them back into water while charging and prevent the loss of water through electrolysis. The recombining is typically 99+% efficient, so almost no water is lost.

The charging voltages are the same as for any standard battery - no need for any special adjustments or problems with incompatible chargers or charge controls. And, since the internal resistance is extremely low, there is almost no heating of the battery even under heavy charge and discharge currents. The Concorde (and most AGM) batteries have no charge or discharge current limits.

AGM's have a very low self-discharge - from 1% to 3% per month is usual. This means that they can sit in storage for much longer periods without charging than standard batteries. The Concorde batteries can be almost fully recharged (95% or better) even after 30 days of being totally discharged."

The AGM battery can be charged as usual and do not have to be water minded as a regular battery so a trickle charger can be used as a voltage minder with complete confidence. The most common reason that a wet battery looses its water is that one or more of its plates in a cell become shorted by contaminants or warpage that puts the plate together causing arcing (boiling). Many of the modern batteries have very thin insulators between plates and can loose that insulation from defects or rough handling such as a dropping of the bike or other accidents.

One other cavet is that the battery must be fully charged in order for a battery minder or trickle charger to work as someone has stated that it is only for maintaining the voltage level, not for bringing the level up to its maximum.

[Pat Kelly]

I have this same situation happening to me right now. I bought 2 Interstate sealed AGM batteries ($!) for both my bikes. The LG is fine, it will start after sitting for weeks. The E has an electrical drain that I have yet to find. I got a battery tender and it has kept the voltage up. Last week I noticed the charger light was blinking red showing that it wasn;t charging.
Now I am home for a day or two and hope to fine the culprit.

[Ivan]

I don't have a battery tender.

I have a plug in transformer from some electronic device that puts out 12 volts at 350 mA. When the bike is going to sit, I hook that on and let it charge. Not enough current to rid the battery of electrolyte, but enough to keep it from freezing. Plus it cost me ... er ... well.. nothing. My wife's computer speakers don't work any more though.

[CatatonicBug]

I don't have a battery tender.

I have a plug in transformer from some electronic device that puts out 12 volts at 350 mA. When the bike is going to sit, I hook that on and let it charge. Not enough current to rid the battery of electrolyte, but enough to keep it from freezing. Plus it cost me ... er ... well.. nothing. My wife's computer speakers don't work any more though.

That's what I call the "McGyver Method"!

[boyat68]

You need a transformer and a diode, the transformer has to be about 13.2 volts or just a tad higher to tend a 12V battery as the absolute voltage of the cells are 13.4,about 2.23 per cell. The diode rectifies the ac voltage to dc. I suppose that your transformer is really a wall wart that has a diode in it to give you the dc voltage. If you measure the voltage with a meter on DC, it will show somewhere in the 15-16 V range with no load.

[Ivan]

yeah it is a DC output. I know that batteries come in at over 12 volts. I honestly haven't checked the actual output with a meter but I can say the bike cranks over every time after using it.

[The Lorax]

The reason rectified 12vac shows up @ like 15 or 16 vdc is due to the conversion stuff...12 vac is actually the RMS voltage, when a rectifier is put on the output, the dc level is actually closer to the peak voltage (rms * square root of 2). I have brought batteries back from the dead before. I don't think any of the cells were shorted, anyway, I added straight sulfuric acid to the battery not to the full mark, just a little under half, put water in it, charge the hell out of it and presto! it gets by for another season or two. Don't try this at home kids as the consequenses of a mishap could be dire. not reccomending this process to anyone, just sharing that it can be done, but not safely. I only tried it because I'm a cheap SOB and on occaision have more stones than sense, but hey, never a dull moment right. have a nice day and ride safe

[boyat68]

Nothing wrong with adding a little sulphuric acid to bring the specific gravity in line with the voltage in each cell. In the old old days many auto shops use to rejuvenate batteries. They would dump the acid mix out of the cells, then bore a small hole in the side or bottom and back flush the plates to dislodge sediment, plug the hole, refill and recharge. After all a battery was very expensive compared to the cost of everything else and the salaries people were making, this was an alternative.

[skids]

Pat, if you think that a tiny current is actually draining the battery, you might think about cleaning the key switch.

The E has an electrical drain that I have yet to find.