Battry tender ?

[raaizin]

I have a 3 year old car which I had to replace battery from inactivity. I was thinking of getting a battery tender.

I presently own one of these which I bought about 10 years ago.
http://www.centurytool.net/87151_Century_15_2_100_Amp_6_12_Battery_Charger_p/87151c.htm

Am I harming my battery or car by using this once a month or so. It has an automatic shutoff. I really dont want to buy another gadget(Battery Tender) unless I need to. I usually put it on 2 amps until the green light comes on.

Ray

 

[Carbon]

Good charger. They are not fast about bring up the charge on a dead car battery, but there is no worry about overcharging with that charger. You could leave it on for months. Mine is fixed at 1.25 amp max, but the charge rate goes to a very tiny value when the green light comes on.

If you have the time, they are very kind to your battery.

http://batterytender.com/chargers.html

 

[Jim 5]

For long term maintenance, I'd go with the Battery Tender Jr. from Carbon's link. You can just leave those on year round. You just need to check your electrolyte once and a while. It's a true float charger.

The one you linked to looks good for a do-all charger but it might be a little bulky for long term maintenance. I like putting the Jr. on and just forgetting it on my motorcycle. I do the same thing all winter on my travel trailer battery with a similar 1.25a float charger.

 

[Panzerman]

I went to Harbor Frieght and you can buy the same maintence charger for about $8, I bought mine for $5 on sale. The battery tender costs about $30 and it looks the same. I use it for my quad batteries and after about a year, it seems to work really good. Hasnt fried any yet.

 

[Carbon]

Originally Posted By: Panzerman
I went to Harbor Frieght and you can buy the same maintence charger for about $8, I bought mine for $5 on sale. The battery tender costs about $30 and it looks the same. I use it for my quad batteries and after about a year, it seems to work really good. Hasnt fried any yet.


Having something look the same at Harbor Freight doesn't mean it similar, except in appearance. In this kind of thing, the copying may be incomplete.

 

[raaizin]

Jim 5, I have the charger on a shelf. All I do is lift hood and attach to the 2 posts Audi puts under hood to jump car(battery in trunk) If I keep it on 2 amps isnt it doing the same as the battery tender. Car usually gets used once a week. In winter it may sit for a couple of weeks if weather is really messy.

Ray

 

[heypete]

Originally Posted By: raaizin
If I keep it on 2 amps isnt it doing the same as the battery tender.


Depends on how long you keep it charging. If it's set to output 2A at all times, you can easily overcharge the battery. "Float" chargers detect how charged the battery is and reduce current so that the battery always is fully charged, but is never overcharged.

 

[gogozy]

how is this one from Sears? http://www.sears.com/shc/s/p_10153_12605_02871219000P?keyword=battery+charger

 

[Blokey]

Originally Posted By: heypete
Originally Posted By: raaizin
If I keep it on 2 amps isnt it doing the same as the battery tender.


Depends on how long you keep it charging. If it's set to output 2A at all times, you can easily overcharge the battery. "Float" chargers detect how charged the battery is and reduce current so that the battery always is fully charged, but is never overcharged.


Correct. BatteryTenders are not like battery chargers, they put out a lot less current so they can't overcharge. I have a BT Jr. on my Porsche. There's no danger of overcharge with the BT Jr. because the float charge current is only 750 mA. On my G8 I use an AutoMeter Battery Extender and its float charge is only 250 mA.

 

[HTSS_TR]

The OP charger can do "automatic 12-volt settings to shut output OFF at full charge, but turns the unit back on if the battery discharges for any reason."

If it does that then the battery will not be overcharged.

 

[doitmyself]

I agree with with HTSS_TR. The OP's automatic charger at 2 amps will gently keep the battery charged without harm and will get the job done, especially if he doesn't want to buy another one.

You MIGHT squeeze a bit more life out of the battery with a "smart" charger that reads the battery condition better and applies the correct charge "better" and "claims to desulfate the battery. But, I emphasize the words "might and claims", because all I have to go on is the anecdotal stories and mfg. marketing. I have the following charger:

One such charger (and there are many) is the Battery Minder:

http://www.batteryminders.com/batterycharger/home.php
http://www.batteryminders.com/press_room/battery-charger-maintainers-which-is-the-best.pdf

 

[raaizin]

That is pretty much what I was thinking. Marketing has a great way of letting us know all the things we NEED. My unit shuts when batt is charged. The battery tenders MIGHT add a few months to the battery, but who really knows. I just hate to have another thing in the garage that I really dont need.

Ray

 

[mechtech2]

Any charger thoughtfully and properly used will keep your battery in top shape.
For stored cars, automatic low amp chargers are handy.

 

[Jim 5]

The nice thing about a battery tender Jr. is that it comes with a dual pole SAE connector and a set of aligator clamps and ring terminals for charging. You can mount the ring terminals to your car and just cable tie the outlet to a opening in the front of your car. When you drive up, you just plug in the BT to the wall and plug the BT into the SAE plug you've mounted on your car.

No tripping over a bulky charger, opening the hood etc.