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Deltran Battery Tender Junior

gerryvz

Site Honcho
Staff member
In November 2012, I bought a trio of the Deltran Battery Tender Junior models off of Amazon.com. They were on sale, and I thought they would be useful for my motorcycle, and E500, and other vehicles as needed to maintain a battery charge particularly in the colder winter months here in south-central Texas (i.e. Dec-Jan, 30-50 degrees F).

These are the small, plug-in units that go to the wall and extend to the vehicle with a charging cable. Amazon has them for around $27 each.

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A couple of years ago, one of the Battery Tender Juniors (which I'd used to keep my motorcycle battery charged) failed somewhat unexpectedly, giving a constant blinking red light and refusing to charge. I threw it out after confirming that it was bad.

Last week, the second Tender Junior failed, which had been used MUCH less than the motorcycle unit. I have used it constantly since the fall to keep the battery in my E500 charged, however.

This is an unacceptable failure rate for this particular product, and I would highly recommend that folks NOT buy it, and instead spend a bit more money for a more robust Battery Tender unit. They make several units in their product line for cars, and all of the other products are more robust.

I settled on purchasing two of the Deltran Battery Tender units. These are much larger and more robust, and properly vented with a metal housing. They cost around $49 each, but the fact they use larger components, and are better vented, should make them last much longer.

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I wanted to make folks aware of this, because these are important for those of us who don't daily or weekly drive our E500Es. :approved:

I'm sure there are many other brands of these battery maintainers out there, many of which are quite good. I know that Griot's Garage has a good battery maintainer product, although it is overpriced IMHO.

Hope this info is of use to someone. :shocking:

Cheers,
Gerry
 
Thanks for the update, Gerry. I agree, ~4 years of intermittent use should not result in failure. :(

I have several different brands of battery maintainers/conditioners, I'd need to double check but IIRC it's two Duracell brand, one Craftsman (10+ years old!), one Deltran (Junior?), a Shumacher or two (flaky, but still mostly working) and three PulseTech Xtreme Charge (one is dying, others still OK).

In general I'd recommend leaning towards a unit that also includes a pulse-type conditioning function. There are a number of brands which offer this, the downside is higher cost - they are generally in the $50-$100 range instead of the "standard" $30-$50 maintainers. The conditioners help keep the battery desulfated and can extend battery life by a significant amount.

:shocking:
 
Thanks Gerry. FWIW, I have two Yuasa SmartShot 900 mA units similar to the BTjunior units that have been in pretty much constant use for 7 or 8 years now. I just recently purchased a Pulsetech Extreme which conditions as well as keeps charge, mostly because of it's favorable reviews and GSXR's recommendation. Pricing is in the low $60 range via Amazon. Another good option is the CTEK 4.3 MUS.
 
I also bought two BT juniors at Harbour Frieght for $12 each and had one go bad within about 3 years. Same blinking light.

drew
 
Yup i second the ctek brand. I have several ctek mus 4.3's that I use on my cars. They are multi stage and have a "brain" so they don't keep charging when the battery is full. They also have a "deep conditioning" option that somehow reconditions a battery.

also you can buy easy plug and play ends....typical battery crimps...or they have eyehole leads that you can permanently attach to your cars battery so then when you want to charge you just plug the easy connect charger end to the easy connect lead on your battery and bingo!
 
Been using two of the larger Deltran tenders like your second photo for several years now, no issues. Have dropped one off the lip of the trunk of the 500E onto the garage floor more than once and no problems. So thumbs up from me.
 
I use CTEK chargers & have done so for 10+ years. Indeed I got my first charger free with a magazine subscription when CTEK first came out. They have several charging modes depending on the model.

Using a battery load tester I recently diagnosed a failing > 2 year old 900amp battery in my 500E. I used the 'recon' cycle of the CTEK and the battery has ever since passed the drop test with flying colours. And these chargers can be hooked up with their own fly leads for quick connections to the car when laid up.

I also highly recommend folks to invest in their own battery drop tester. A hugely useful bit of kit for diagnosing a battery & charging problems. Or just proactively keeping an eye on the battery condition.

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I don't have any long term data, but I'm pleased thus far with this desulfating unit.
 

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FWIW, I've had 2 Battery Tenders and 1 BT Junior (all for over 10 years), all are still working.
Have you used the BT Jr. consistent or intermittently?

I also have a hunch that BT has majorly reduced the quality (overseas manufacture) of their units from 10+ years ago, but that's just a hunch.
 
Have you used the BT Jr. consistent or intermittently?

I also have a hunch that BT has majorly reduced the quality (overseas manufacture) of their units from 10+ years ago, but that's just a hunch.

I used the BT Junior consistently for the first 5-6 years I had it (on an auto battery). After I sold a bunch of cars, I switched it to a lawn tractor battery (last 5 years or so). The regular BT's are used consistently on autos still.
 
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I've been using BT Jrs for years. The 500E is on one right now. I use them constantly for months at at time during winter storage, and usually connect the pigtails when garaged after regular driving.

I must've got mine during a better production run. I've only had one die prematurely (...I drove over it twice. 500E is pretty heavy car. The Deltran took the first offense in stride, but the 2nd time was a touch too much :hammerhead:).

However, I do need to get a legitimate modern battery charger one of these days. The heavy duty old school chargers I inherited from my father have finally shat the bed after a more than respectable 40 - 50 year run & are now officially decommissioned from service.

They were pretty cool, though. Looked like something you would hook Frankenstein up to.
 
I have a BT, but I did notice this past christmas they were on the holiday tool isle of either Homedepot or lowes... $19.99.
 

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