Battery Tenders...What Kind To Buy...

I get asked fairly often about battery tenders, and what kind we use on the cars entered in the Great Race. Well... we have used the same brand for the past 30 years simply because they work. We have tried about every brand, the cheaper to the more expensive but have always come back to the Battery Tender brand because they are simple, they are durable, and they work.

First off we need to talk about why you should use a battery tender in the first place. A battery tender will keep your battery fully charged while your antique vehicle is parked in storage. If you get a good one it will compensate for any parasitic draw such as from car radio memory or an accessory that runs in the background.  Their use is not limited to antique vehicles, they will charge and maintain any battery from your riding lawn mower to your 1950 Buick.

The difference between a battery tender and a small trickle charger comes when your battery becomes fully charged. A trickle charger or small battery charger either charges or it doesn't... so it has no way to "Float" a battery which means just enough current output to keep the battery fully charged... but not overcharged or undercharged.

A trickle charger or small conventional battery charger turn on and off as a way to try and maintain full battery voltage. The result is the battery gets over charged then sits and becomes discharged then the battery charger begins to charge again. The constant charging and discharging shortens the life of the battery, and there is no way to compensate for a parasitic electrical load.

In contrast a battery tender provides a steady voltage that is just enough to maintain proper battery voltage so the battery is always a peak charge. A battery tender will not over charge a battery. That makes the battery last at least twice as long because it is not constantly being charged and then discharged. It is kept at a steady voltage. It also prevents any damage to the electrical system of your antique vehicle while it is in storage.

The technology of how batteries are manufactured has changed a lot in recent years (mostly for the better) and now many of the batteries you buy are the AGM or absorbed glass mat type (Optima) or a Gel battery. So now we need a battery tender that will charge all three types of batteries, the old school lead acid battery, the AGM type, and the Gel batteries.

While we are at it a faster charging rate would help with the AGM and Gel batteries which take a little more current to begin charging. It makes a conventional battery charge much faster as well, Twice as fast to be exact, as compared to the previous design Battery Tender.

The new Battery Tender shown above will also charge BOTH 6-volt and 12-volt batteries...so now you no longer need two different battery tenders, one for 6-volt and one for 12-volt. A battery tender should also come with the correct accessories including...

You should expect to have the short leads in a wiring harness that you can attach to the vehicle battery that hide when not in use, then when you plug into your battery tender you do not have to open the hood  to make connections. The wiring harness that comes with this battery tender is made so it only plugs in one way so you can't get the connections backwards. 

You should also have a wiring harness available for your battery tender for temporary connections to charge a battery most anywhere.

Both types are included with the battery tender shown above. The warranty on this new Battery charger is 5 years. The AC cord is 6 feet long and the battery to charger cords are 2 feet long, which is long enough reach for most applications. If you are into the numbers game here is the physical size of the new Battery Tender

And the specifications...

I have only three of the original old school Battery Tenders left and all three are 12-volt. The 6-volt ones are all gone. So it you want a Battery Tender of the old school design you had better act fast.

If you have one of the old school design Battery Tenders, all of the wiring harnesses from your Battery Tender will work with the new design Battery Tender. If your old school Battery Tender is working fine might as well keep using it.  But... when the time comes to upgrade you now know what you need to buy, and life will be good once again.