From the little bit of time on the forum I see that the CTek charger is the predominant equipment choice. I've been thinking that I need to get set up for topping off the battery to keep the gremlins at bay. There may be weeks parked during the cooler and wetter months in northern Georgia.

The CTek is running at $95 +/- and the connectors are sometimes extra.

Who is using knockoffs for charging? I see full featured units for a third of the cost and I'll bet that they're all made in China maybe even on the same factory line.

 

dup

 

A couple things. First, we use battery maintainers, not trickle chargers. There's a difference. Sometimes they're referred to as smart chargers. This is the one I use:




Yeah they aren't cheap

 

The CTEK units are not the only “Smart” maintainers, but they are among the best. I have used them for years. They can be left connected indefinitely and safely with no fear of overcharging and with confidence that the battery will remain fully charged. I cannot say the same for a competing brand which I also use.

 

Thanks guys, I guess my age is showing when I called them trickle chargers. My '92 Miata would hibernate in the northern Illinois winters and come out about a month after the groundhog.

It also had an AGM battery located in the aft end and it lived on a charger after I had to replace the expensive battery.

I think that all of them now have the overcharge circuit.

 

For many years I’ve been using a Battery Tender brand maintainer on my XK (not the ‘Jr’ version, but the regular in the metal chassis). Several years ago I bought another, and it serves my Lexus. Thinking I should try the Ctek, I bought one (MXS 5.0), but it’s not very unreliable. A couple of times the error light would come on, so thinking my battery should be changed, I bought a new battery. Put it on the Ctek for about a week before I had a opportunity to take a drive, and I notice my voltage level while driving was lower than normal (usually ran at 14.2, but now it’s running 13.8).
I switched back to the Battery Tender unit, but haven’t had a chance to take a drive again to verify the difference. So as of now, I’m not convinced I’ve got a good Ctek, might have a bum one.

 

Battery Terminology Matters! There's are big differences between (1) a trickle charger, (2) a battery maintainer, and (3) a battery charger.

A trickle charger is dumb. It continually applies a small charge to the battery, and once the battery is fully charged it will keep charging it at the same, constant rate of charge. That can overcharge and damage a flooded (a.k.a. "wet cell") battery by boiling out the electrolyte.

A battery maintainer is smart. It incorporates circuitry that monitors the battery's state of charge and automatically applies varying levels of charge to keep the battery fully charged without overcharging it. Many people call it a "Battery Tender", but that is the brand name of a battery maintainer that I don't recommend. Read my Amazon review of the Battery Tender Jr. that I bought for my XKR:
I recommend the CTEK brand of battery maintainers. They have several models with varying features, and I am very pleased with the CTEK MUS4.3 that I have been using on my XJ because its Recondition Mode worked to resurrect my Stop-Start auxiliary battery. I've also been using a CTEK MUS4.3 on my XKR after I replaced the flooded battery with an Interstate AGM battery from Costco. There are many other quality maintainers on the market, but Jaguar sells the CTEK 3300 as an accessory with its Leaper Logo. You can buy it for less on Amazon without the Jaguar logo.

If your battery is dead, you'll need a Battery Charger with an output of at least 10 amperes to recharge it. Battery maintainers and trickle chargers simply don't have enough output oomph (amperage) to charge a dead battery in a short time.

Weather extremes - Florida summers and Alaska winters - wreak havoc on battery longevity. And once a battery goes dead, it's doomed even though you may have been able to recharge it.

Battery type also matters, but that discussion is for another thread.

 

There are many brands and types of battery charger which is why I have a large collection of smart, bulk and trickle chargers built up over the last 50 years. In recent years the smart charger, which effectively replaces a trickle charger and some of which can also replace a bulk charger, has become the go to device. Apart from reliability and ultimate power output, an important consideration is whether the charger will restart after a power outage or brown-out. I think that all bulk and trickle chargers will re-start but not all smart chargers will, which might be important in some circumstances.

Richard

 

"Smart" charger, be it 1/2 amp or 50 amps -- Stop when battery full

"Trickle charger, normally low amps -- Charges forever

"Maintainer", low to medium low amps -- Charge at varying levels until full, then vary between charging and not charging at various methods according to the battery condition at all times. Called "Float" on some models.

 

I have a few different brands that I use on my cars: Some I've had for many years (Deltran tenders). Ctek, Noco, a Porsche-branded tender, and a couple of Deltran Battery Tenders. They've all worked fine, but of those I would recommend the Ctek. A little pricey, but great quality, simple, and good options for connections.

 

I'm guessing that nomenclature changes across either side of the pond as over here we refer to battery chargers as being "smart" or "intelligent" where they switch to a lower voltage once the battery is fully charged and has reached gassing voltage. We do not generally use the term "maintainer" in this context.

I'm not familiar with any chargers which switch off and deliver zero voltage once the battery is fully charged. Once the voltage starts to drop due to natural discharge, does the smart charger switch back on again?

Richard

 

@kj07xk , your input sparked my interest.
As you are aware, the generator’s output is dynamic based on need. I interpret your situation as it seems that after your charging effort, less “need” was required of the generator. So I submit the argument that your battery was finally up to snuff.

As we have discussed to nauseam, think of the generator (“alternator” on this side of the pond) as a maintainer. Not a charger.

food for thought.
Cheers.

 

As a new XK8 owner I was surprised to learn that it seems a lot of people use the battery tender whenever the car is in the garage to avoid electrical issues. I understand if the car sits for a while this is beneficial, but surely if the car is driven daily or even weekly this should not be necessary. I admit, I bought the car purely for the looks and will bear the maintenance issues as they come up and if keeping the battery on the tender is the way to avoid issues, I will get one. Any thoughts from experienced XK8 owners on this?
Cheers.

 

Gaining ground in this field is the NOCO Genius brand. I chose the 2amp model. Works well and claims to do pretty much everything.
I'm running a larger than original equipment AGM battery, so the standard alternator is not the best match, and I can't expect it ever top up the battery.

 

The result of low battery voltage in modern cars can very often, most often be confusing because the symptoms are random - they can be in ANY system of the car in which electronic modules are involved - and that means almost any system. Thus random warning lights, non-functioning electrical items,....almost anything. And it is for this reason, the need for full battery voltage all the time to power the modules, that EVERY luxury car manufacturer, every one, markets the CTEK maintainers under their own labels . Want proof?:
AUDI:

ROLLS ROYCE

well, the CTEK unit labels speak for themselves:













OK....I think you get the message....battery voltage is crucial to avoiding issues.

So, many of us use a battery maintainer on a permanent basis, that is the unit permanently wire to the car's charging system - very easy: one wire (-) to any ground point, one wire (+) to the battery monitoring block OR for cars built before 2010 or thereabouts, directly to the battery. Using the maintainer then becomes a 3 second bit of work simply connecting or disconnecting the CTEK unit wire to the permanent wire connection.

My F-Type resting in the garage: note the CTEK connector at the trunk panel edge, and the CTEK unit on the wall. The result? never any electrical issue real or apparent cause by low battery voltage. These maintainers can be left connected for YEARS at a time. They will never overcharge the battery.

 

Thanks sov211. This is my first venture into the luxury car segment. I'm convinced and will be getting one for my XK8. Cheap insurance as far as I'm concerned. Just seems nuts that you need it for luxury cars, but 'cheap' cars do fine without...

 

I had an XK8 for years and never had a battery problem. However XK8s, being older designs, have a LOT less electronic equipment in them.

 

“Battery Tender” is what I’ve always used on my Harleys, and what most other riders and Harley dealers use. I’ve never had an issue with one, so, when I got my XKR this is what is got, it has enough oomph to bring the battery back up to full charge when I accidentally forget to plug it in for a while.

 

You can frequently find the CTek on Amazon (or its clearance outlet, woot.com), always with all connectors, for around $75.

 

Over 700 people on Amazon found my Battery Tender review helpful. Read why I will never buy another Deltran product again.

I didn't get angry. I got even.
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