Could some one be so kind as direct me in the right place to find out other ways to charge my flight box battery. I have looked but must not be looking in the right places. Looking to charge them without the worry of over charging. Looking for some way to charge it where the charger shuts off. Am new to this and do not care for the plug in charger that came with the 7ah I bought. I am sure there is info in the forum some where, Just cant find it.

I have an ACE CVC (constant voltage charger) that I'm pleased with. It has two advantages over the wall wart that came with your battery. It has an LED that tells you when the battery is charged and the power supply is larger and does not get as hot. You can leave these on charge all the time because the amperage drops as the battery is charged but if you don't want to just put it on a 110 timer which you could do with your wall wart as well. After it is charged just give it 30 minutes a day and it'll always be topped off and ready.

The correct way to charge any battery is to refer to the amp/hour rating of
the battery. For instance, if the battery is a 10 amp/hour, and needs charged
you would charge it at 1 amp for 10 hours. If you had a 500 milli-amp charger
( 1/2 amp ) you could charge it for 20 hours.

Excess charging will not help the battery, it will harm it. This is where the timer
comes in handy....use it to set the charging time, and do not over charge it.

FBD.

The flight box battery isn't the only battery you'll be charging.

While it is decidedly more expensive than a wall-wart, you probably should look into buying a multifunction charger, such as the Great Planes Electrifly Triton.

The Triton is fully automatic in terms of charge termination. It also has manual modes, as do most other high end chargers.

The best thing about the Triton (and other similar chargers) is that it will correctly charge Pb, NiCd, NiMh, Li-Ion, and LiPo batteries.

A good web site to know about is [link=http://www.rcbatteryclinic.com/]Red Scholefield's Battery Clinic.[/link] Several charger reviews, and battery wisdom dispensed by a battery engineer.

Do a search for "battery tender plus." I have one of these to charge my flight box battery, and it works very well. You can get them online from several vendors, including ebay.

This forum probably has the most misinformation of them all.

Dave,
While it is true in theory what you said about charging times in actuality you need to charge about 20% longer than capacity to achieve a full charge. Now since the flight box batteries are probably never fully discharged you really wouldn't need to charge them that long but for the sake of the explanation it should be made clear. Also it is hard to "overcharge" a Gelcell with the correct CVC chargers. The amperage drops off a maintenence charge, just like a car charger.

Fred,
While the Triton is an excellent charger it isn't practicle for a Gelcell on a regular basis. As you said you probably have more than one battery to charge so to leave the triton on the gelcell will mean you can't use it on your other batteries. Also the automatic settings are hit and miss and I don't trust them, I have seen several Li-pos puffed from using the auto mode. Unless someone is will to take the time and effort to learn how to use it I advise against it. It's best use is for conditioning and testing of batteries, li-pos on manual mode and field charging.

Yo BB....

....the man stated he had a "flight box battery"....nothing more.

My offering:

"The correct way to charge any battery is to refer to the amp/hour rating of
the battery."

....is correct in any case, on any battery. Aside from giving a genaral idea of the
"power" of the battery, the amp/hour rating reflects the chaging rate as well.

That isn't missinformation....it's a fact.

FBD

Come on Dave, we both know a 7amp/hour flight box battery is a Gelcell. Also, while the amp/hour rating does determine the charge rate it doesn't necassarily determine the charge time.

I did not want this to come to a fight about who is right or who is wrong. I just needed info on alternitives to the wall charger. Some times I forget about the battery being on the charger when tending to my childrens needs. I was looking for info on what you fellas use to charge your flight box batteries that will bring it to peak and then trickle charge but not over charge. The info that has been provided so far has been just what I was looking for. Thanks for the help, and any more ideas would be great.

Welcome to RCU.

The charger that came with your battery will not vary the charge rate. The best
thing to do is use a timer to cut off the charger, so it will not over charge. [sm=thumbup.gif]

Use the guideline I showed in post #3.

FBD.

Fom the Battery Clinic

http://www.rcbatteryclinic.com

Care and Feeding of your Sealed Lead Acid Battery
(aka - gel cells)

Lead Acid (Gel Cell) charging

Lead acid (gel cells) should be charged with a constant potential charger specifically designed for these batteries. These are sometimes referred to as a CVC charger. You can charge them with a constant current charger but you must terminate charge when the voltage reaches 14.7 volts. You should not exceed the C/10 charge rate. If you have a 7 Ah battery in your field box the maximum constant current charge rate should not exceed 700 mA. It will take about 14 hours to charge from a fully discharged state (voltage less than 12 volts).

A CVC (Constant Voltage Charger) is exactly what the name implies. It is clamped at a certain voltage and puts out all the current it can until the battery reaches the clamp voltage, usually something around 14.5 volts, then the current drops off to maintain it at this voltage. A constant voltage charger is characterized as one having a current capability of supplying a fixed voltage to whatever load is applied. A constant current charge on the other hand will provide whatever voltage is necessary to force a fixed
value of current though a load. Constant current charges have a much higher internal resistance than the load so that any variation on the load will not change the current being supplied. Constant voltage charges have a very low resistance as compared to the load and will supply whatever current necessary to maintain a given voltage at the load.

Many inexpensive chargers used for sealed lead batteries are what is called taper chargers, these are set up so the voltage tapers off as the full charge voltage is reached. True constant potential ( CVC ) chargers can be quite expensive so a compromise is made in the design to control costs.

We have used the term sealed lead battery in this discussion. These batteries are not truly sealed as cylindrical Ni-Cds are. They have a gelled electrolyte system where there is a modest recombination of the oxygen in overcharge in some designs. All require venting of the oxygen and hydrogen byproducts of charging and discharging. This is why you should never totally seal these in a field box where these gasses can accumulate. Mixtures of oxygen and hydrogen can cause spectacular "events" if a spark is provided (from an electric fuel pump motor).


How much charge is there in the battery?
Unlike Ni-Cds you can read the remaining capacity quite easily with a voltmeter.

After the battery has been on rest for a few hours read the voltage (no load). 12.0 volts is essentially fully discharged while 13.0 is fully charged. This is a fairly linear relationship so a reading of 12.4 volts means you have 40% of the capacity remaining.

Never leave a lead acid battery in the discharged condition.
The lead acid battery should never be left to set in the discharged condition or sulfation will result. The sulfuric acid in the electrolyte reacts with the sponge lead active material and forms lead sulfate. It is a poor conductor. This coupled with the H2O left after you take all the S out of H2SO4 is also a poor conductor so trying to charge requires a lot of voltage to push the current through required to convert the active material back to the charged state. Sometimes they just cannot be brought back from the sulfated state.

The good news is that sealed lead batteries retain their charge much longer than Ni-Cd. At room temperature it's well over a year. So all you have to do is make an occasional open circuit voltage check to see if you need to charge it.

Yo, BB....you need to study-up. The amp/hr rating for a battery gives the
dischage rate, or "power" of the battery. For example, a 7 a/h battery will deliver
1 amp for 7 hours....that is the batteries rating. A good guideline for charging the
battery with out overheating it (and damage) is to use the a/h rating for charging.

BTW, I learned this technique for battery charging at the Yamaha factory training
school in 1970, and it has worked perfectly for my lifetime.

If you have a better idea on rating or charging batteries, won't you spring it on
the World post haste ?

The "flight box battery" in question is most likely a "sealed lead acid type", not a
more expensive gel cell....although it could be a gel cell, but I doubt it.

See this:

http://www.zbattery.com/zbattery/ub1270.html

....this is probably what he has.

Here's a battery factoid you might want to store in memory. Lead and wet/acid
batteries....as well as gel cell batteries contain acid. The only difference is the acid
is in a gelled form, so it is safer and wont spill. Sealed lead and wet acid batteries
look like some gel cells.

However , the a/h hour ratings for them are the same, as well as the discharge and
charging rates.

FBD.

Yo, BB....that was an excellant copy and paste job....I'm impressed.

FBD.

Well I did copy and paste it with all credits included. If you read it you will see several points we have discussed.

Lead acid and Gelcell are the same thing.

C/10 is the charge rate, in this case 700ma for a 7 amp battery or 1/10 capacity but the time is not 10 times for a complete charge more like 140% or 14 hours.

Battery technology has come a long ways in the last 36 years.

The battery is a Hobbico TorqMasterLC. I found a charger at Tower that will work at home to charge and do what I need it to do. I do thank you for the battery info. Used that inf to find the charger that would do what I wanted it to. And it will charge my tx/rx too. Thanks again for the help. Just had to get the wife to let go of a little more cash to get the better charger. I think it will be money well spent.

Good luck with your flight box, and I hope you enjoy RCU.

FBD. [sm=thumbup.gif]

http://www.batterystuff.com/tutorial_battery.html#3

Indeed.

Ok, the originator should buy a Battery Tender. That'll take care of maintaining the charge in his Pb flight box battery, which by the way does not exhibit self-discharge to any significant degree.

When he wants to put his Rx and Tx packs on maintenance charge, he can go get an appliance timer and just use his OEM wall-warts to put the NiCds or NiMhs on floating charge as well.

If we assume he might also have rechargeable batteries in his digital camera, video camera, cell phones, cordless phones, TV and dish remotes, and a half-dozen other household appliances, he can get timers and do the wall-wart thing with them as well.

Down the road, the modeler won't be very satisfied with Battery Tenders and wall-warts/timers because his rechargeable batteries will have quite literally been tickled to death.

I've never done that of course. I've never had to replace two 9Z packs because the 1100 mAh NiCds died from internal shorts caused by maintaining them with wall-warts/timers. I've never lost high capacity flight packs due to 'whiskers'.

I have an Accucycle, Fast Field Charger, and an Einstein collecting dust on the shelf. I have 6 Battery Tenders (found 'em on sale at Harbor Freight a couple years back). They're collecting dust as well.

As for the Triton being difficult to use, "She" found my 4 Tritons in the shop and stuck out her lip. I'm not stupid, so there's a Triton in the house also.

If a Redheaded left-handed database administrator can figure out how to use a Triton to deal with all the rechargeable batteries in a reasonable well-appointed house, there is absolutely no reason a model builder/flyer can't master the thing.

As for Tritons turning LiPo packs into puff pastry, what's really true is that there are some people who eat at McDonald's because they can't manage grilling a burger without setting the house on fire.

But like you said, there sure is a lot of misinformation in this group.

Fred,
I have a Triton myself. I was commenting on your suggestion to use it on auto mode which I think is a mistake with li-pos based on a friends experiance. I recommended a CVC charger for the Pb battery and the timer on a wallwart for a cheaper alternative. I think every modeler should have something at least as good as the Triton for cycling/conditioning but it is not practicle for the average modeler to use it on all his batteries all the time.

Well....lets have a look at some of this "missinformation"....shall we ?

Here's a battery out of my sisters motorscooter....it's a five amp battery
as you can see. It is of course, a lead acid battery, made basically the same
(except for the plastic the case is made out of ) as the first lead acid battery's
were made a century ago.

Look at the instructions for a standard/normal charge. Notice the charging rate is
exactly as I said....1/2 amp / 5 amp battery / charge for 10 hours.

Or, if you had a 1 amp charger the time would be 5 hours.

This formula works fine on all lead acid batteries, including gel cells....even though
our new found battery experts think this Forum has mostly missinformation.

Flyboy Dave

....oh, really ? Wrong on both counts.

Actually it says 5 to 10 hours so that doesn't really support your theory does it? It also says to charge at 5 amps so again it isn't helping your case much at all.

Now you better go put it back on your sisters scooter before she finds out what you have been up to.

OK....I guess you are absolutely clueless about batteries, I suspected that from
the start. The first thing I suggest is....learn how to read a battery's designation.

( Handy hint: this is the part number as well )

GS in the brand name. GTX5L-BS is the manufactures part number as well as the
batteries size or "designation". In other words, you could go to anyplace where
they sell these small batteries, and ask for a GTX5L battery, and the counter person
can look it up by that number.

Secondly, you might want to take a refresher course in arithmetic.

.5 amp times (X) 5 amp/hr ( the battery rating ) = 10 ( ten hours )

Just exactly what is said twice before. You seem to be slow at catching on to this
battery stuff.

I would not have mentioned these shortcomings had you not been so negative
and such a know-it-all smarty pants and dissed the Members that were trying to
offer decent advice. Better luck next time.

FBD.

What does the batteries part number have to do with this discussion?

Thanks for the math lesson but you forgot about internal resistance, heat and that batteries don't charge by the linear equation you described. Why does Red say to charge 14 hours in his example instead of your 10 hours?

I still love ya', BB....

This one's about had it. [sm=surprised.gif]

FBD