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Trickle charger vs. battery tender

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AUSMHLY

AUSMHLY

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I just ran across an item called a battery tender.
I recently heard that trickle chargers are not that good for a car.

Does the "battery tender" seem like a better alternative?
Here is the link: https://batterytender.com/

Doing a search found cheaper prices than their home page.

Merry Christmas,
Roger
 
By definition, battery tenders or float chargers use a lower voltage with very limited current. They are "better" than a trickle charger in that they evaporate the electrolyte out of the battery slower. You should still keep an eye on the battery fluid level though, even with a battery tender. I have used the less expensive float chargers from Harbor Freight for several years with very good results.

Merry Christmas!
 
Roger,

You will like the battery tender once you use it.
It makes charging batteries almost bullet proof.
I have had one for several years, use it on the jet ski battery all winter, also used it on the optima battery on the Healey once after the battery was completely discharged with excellent results.
I use to have to buy a new jet ski battery every other year.
Since I bought the battery tender and have hooked it up to the jet ski battery over the several winter months of no use, I am still using the same battery that I had when I bought the battery tender. ( about four years now ). In the case of a car battery that is completely discharged, it takes a day to slowly recharge it with a battery tender but it doesn't overheat/boil the battery with a high amp charge
like a standard type of battery charger. Many people I know use them on their boat batteries when in storage.
.... Merry Christmas !
Ed
 
Ed_K said:
Many people I know use them on their boat batteries when in storage.
Click to expand...

I have Battery Tenders on four cars and a boat. All work perfectly. I start each car once per week, but the boat often goes many months between uses, and it has always started immediately, in one case even after sitting for almost two years!
 
Does the battery need to be disconected to do this or will the battery shut off do the job? How cheep is the Harbor Freight version? You all have convience me not to start her up till operating temps are reached every week.
 
Any one using a solar unit? If so, is it a float type? (Garage has a window) We are expecting 4 to 10 feet of snow this weekend which makes taking a spin an imposible.
 
Every winter since 2004 I've taken both the six volt batteries out of the BN7 and clean them, and the mountings where they sit, top up with distilled water and charge using a regular battery charger set on 2 amps. My charger has a shut-off when the battery reaches fully charged. I don't leave the charger on all the time, but I do recharge after about a month. Never had a problem.
 
The battery cut off switch to the off position is good. You can also leave it in the on position as long as you don't have any slow current drain like the memory keep-alive of a modern radio.
Ed
 
Installed one in my BN1, works well, have the batt switch in the off position just in case there is a slow drain somewhere (doubtful in a bare basics BN1!), just gotta check the electrolyte levels now and again, is just a plug in the mains extension cord and leave, its a projecta ac250b
 
Moss has an "on board" float type charger for $56.00. K-mart/Sears has one for $29.00 and Harbor freights is 10 bucks. The Tender is in there somewhere. The Sears one has clip on as well as screw on attachments. I cannot determine the amps on any of these. I already have a 10 amp charger that I never use. I do not believe it has a shut off for full charge. Is this a case of you get what you pay for? Thoughts on the best for our needs?
 
It's not a question of the amp capacity of these battery maintainers. It is a question of how they sense the charge state of the battery and then adjust themselves to lower the current when they have sensed that the battery has reached it's maximum charge. They are all supposed to perform the same sense/current regulating function.
The old style battery chargers did not have the ability to sense the state of the battery being charged nor were they able to lower or limit the current that they were supplying
to the battery. The result was that the old style charger would completely charge the battery and then continue to provide current which would result in the electrolyte being evaporated. When this happens, it leaves a bridge of residue between plates of the battery resulting in a shorted battery that needed to be replaced. I supposed that there is a difference in the maximum charge capacity of these maintainers but all that would really mean is that the battery would reach the maximum charge state a little more quickly than a lower capacity maintainer. The time that it takes to reach the maximum charge is not why you want to buy one of these. If you have a dead battery and want to start your car asap, get the largest amp old style battery charger that you have and hook it up.
 
tahoe healey said:
Moss has an "on board" float type charger for $56.00. K-mart/Sears has one for $29.00 and Harbor freights is 10 bucks. The Tender is in there somewhere. The Sears one has clip on as well as screw on attachments. I cannot determine the amps on any of these. I already have a 10 amp charger that I never use. I do not believe it has a shut off for full charge. Is this a case of you get what you pay for? Thoughts on the best for our needs?
Click to expand...

The direct answer is that you buy/use these for long term battery storage. You hook one up to the Healey in your cold garage when there is ten feet of snow outside. Then you plug it in and forget it. When spring time arrives and you can see your yard again, you can unplug the tender, jump in your car and it will turn over just as fast as it did the day you stopped driving it last season.
 
Long ago, about 35 years, I built an adjustable voltage output regulator into my Sears 10 amp charger. Once a battery is fully charged, I simply adjust the regulator to only turn on if the battery is a bit low. If left on the battery continuously, it turns on a few milliamps once in a while & then cuts off again. On a low battery, it will put out 10 amps, taper off to about two, & then cut off as in the "tender" mode.

I'm guessing that this is how the "tenders" work?
D
 
Hi Dave,
That is my understanding of how it works. Once in a great while after a battery has been fully charged, I notice the red light flash on for a little while then back to a solid green,
( fully charged ). The red light comes on anytime it is supplying current.
Ed
 
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