Car battery pulsing

[Fred H]

I'm fond of my 2015 Subaru Legacy 3.6, but it has required a new battery every 2 years -- "poor design" according to a recently-settled legal action.

In an effort to mitigate this I installed a Power Pulse 12 Volt Desulfator PP-12-L. When I mentioned it in a Subaru forum I was told: "The narrow, high-voltage pulses intended to de-sulfate the battery can damage the many electronic modules used throughout modern vehicles ... including our Subarus. Subaru of America has even posted memos to this effect in their dealer tech publications."

In their FAC on "Will PulseTech products damage electrical systems on cars and other vehicles?", PulseTech says: "It is not possible for any of our products to damage the electrical system on any vehicle. By attaching the product to the battery, the pulsing energy is absorbed within the battery and is not "seen" elsewhere in the system. This technology has been applied to a variety of military vehicles with very sensitive launching systems or computer systems with no interference or problems."

I still like the idea of doing something. But the "absorbed within the battery" response doesn't make complete sense to me and I don't know enough to evaluate it. The every-two-years battery replacement doesn't affect my enjoyment of the car and the $55 I spent isn't material, but I don't want to damage expensive components. Can someone please advise me?

 

[Owl]

I have been using the C-tek brand charger for over ten years now and have had great results. Most modern chargers have some sort of pulse technology, and are used world wide. The main problem is completing a proper re-charge of the battery. The car alternator in your Subaru may be at he high side for a 12 volt battery, 14.8 volts, this is fine for stop start applications, but you will still need to re-charge completely when the vehicle is stopped. If you have a car garage or safe car port you can plug in the "shore" charger and completely charge the battery, this will increase battery live. My last two batteries lasted seven years and six and a half years, because I re-charged completely every week.

 

[Fred H]

This isn't a battery charger; it's a unit that attaches to the battery and remains attached while running. So it is creating pulses both while the car is running and while it's shut off. If more knowledgeable people that I suggest that it be removed, I will buy a charger and start doing what you have been doing. Thank you, I hadn't considered that alternative.

 

[Owl]

I lived off grid and on battery power for about 14 years, and have never heard of that kind of device. I would recommend returning to basics, a good battery charger and an accurate voltmeter to test.

 

[DVDdoug]

I'm skeptical of EVERYTHING!

I'm skeptical that the thing works. And it's a "difficult experiment". If you next battery lasts 3 years, maybe it's just a better battery, etc.

I'm skeptical that it will damage the car. Manufacturer's usually recommend against ANY modifications and the warranty probably says that any modifications void the warranty, etc.*

I'm skeptical that the pulses are completely absorbed by the battery, but I can believe that they are mostly absorbed by the battery. (It has very-low impedance.)




* Many years ago the small company I was working for was considering getting involved in a joint venture. The owner said they were checking with their lawyer. Later I asked him what the lawyer said, and he said, "Lawyers always say 'no' because there is no risk (to the lawyer) in saying no." I think he went-ahead with it anyway...

 

[Fred H]

My last two batteries lasted seven years and six and a half years, because I re-charged completely every week.

I would recommend returning to basics, a good battery charger and an accurate voltmeter to test.

These seem to fall into the Keep It Simple (Stupid) principal, to which I subscribe.

I'm skeptical that it will damage the car. Manufacturer's usually recommend against ANY modifications and the warranty probably says that any modifications void the warranty, etc.*

I've ignored the manufacturer on the tune, sway bars, bushings and shocks, but I don't understand this as well.

I have been using the C-tek brand charger for over ten years now and have had great results.

I looked at them and was impressed. Their newest "advance" is displaying completion time so their older unit is on sale for $72, after a 20% amazon coupon.

C-tek's range of battery treatments is what convinced me. I'm going to remove the unit and charge with a C-tek once a week. (I have a voltmeter already.) Thank you both.
Fred

 

[AdamG]

I'm fond of my 2015 Subaru Legacy 3.6, but it has required a new battery every 2 years -- "poor design" according to a recently-settled legal action.

In an effort to mitigate this I installed a Power Pulse 12 Volt Desulfator PP-12-L. When I mentioned it in a Subaru forum I was told: "The narrow, high-voltage pulses intended to de-sulfate the battery can damage the many electronic modules used throughout modern vehicles ... including our Subarus. Subaru of America has even posted memos to this effect in their dealer tech publications."

In their FAC on "Will PulseTech products damage electrical systems on cars and other vehicles?", PulseTech says: "It is not possible for any of our products to damage the electrical system on any vehicle. By attaching the product to the battery, the pulsing energy is absorbed within the battery and is not "seen" elsewhere in the system. This technology has been applied to a variety of military vehicles with very sensitive launching systems or computer systems with no interference or problems."

I still like the idea of doing something. But the "absorbed within the battery" response doesn't make complete sense to me and I don't know enough to evaluate it. The every-two-years battery replacement doesn't affect my enjoyment of the car and the $55 I spent isn't material, but I don't want to damage expensive components. Can someone please advise me?

Hi Fred,

I use a Battery Tender for my Truck and Bike. This has two major benefits. 1; it will keep your battery fully charged. 2; it will extend the life of your battery. In most cases I have found this to work great. It’s easy to install. Just a suggestion that might offer a solution that you may not be aware of.

Battery Tender Plus 12V Battery Charger and Maintainer: 1.25 AMP Powersport Battery Charger and Maintainer for Motorcycles, ATVs, UTVs - Smart 12 Volt Automatic Float Charger - 021-0128 https://a.co/d/aTNNX3P

 

[Blumlein 88]

Is your Subaru a daily driver or does it get driven at least once per week? Sulfonization is usually a problem for cars that mostly sit around in storage rarely used.

 

[Fred H]

Thank you, Adam. It looks like a good alternative and has great reviews! I'm going to dither for a bit, but it looks like a choice between two good alternatives.
Also, I appreciate how much you bring to the forum. So thank you for that too.
Fred

 

[Fred H]

Is your Subaru a daily driver or does it get driven at least once per week? Sulfonization is usually a problem for cars that mostly sit around in storage rarely used.

My car is a daily driver, but Subaru's battery record is abysmal. Perhaps the 14.8 volt alternator mentioned by @Owl above is at fault.

 

[fpitas]

I've used a battery tender for many years to keep the tiny battery in my Elise alive.

 

[Philbo King]

+1 on a battery tender. I have a few, one for each electric start engine in my garage (lawn tractor, 8kw generator, wifes almost-never-driven sports car).

Not useful for some hybrid vehicles since they often use the high-voltage battery for startup duty.

 

[Blumlein 88]

My car is a daily driver, but Subaru's battery record is abysmal. Perhaps the 14.8 volt alternator mentioned by @Owl above is at fault.

High voltage would make sulfonation less likely. Not disputing Subaru has a battery issue. I doubt extra charging will fix it, but maybe there are issues that are odd about Subaru.

 

[Blumlein 88]

Had a few minutes to look into the Subaru battery issues. Apparently some Subaru cars don't go into sleep mode like they should. So they draw a bit of current. If you drive everyday the battery still starts, but over time that wears out the plates in the battery from excessive charge and discharge.

So, yes a battery tender would help your situation. Sorry I gave uninformed bad advice. The battery tender would supply current so the battery isn't being discharged. Which would extend the life of your battery to something normal.

Now my uncle has one of the effected models and has no battery issues with his. I'm not sure why some would do this and not others.

Buying the largest capacity battery would help some. It would also probably be less of an issue if you can get a deep cycle marine battery that fits the Subaru. Deep cycle batteries don't have the same oomph in really cold weather. So if you have cold weather not a good solution. If you live in a warm area, that might help quite a bit. They have thicker plates and are made to be deeply discharged without it wearing them out so fast. Rather poor form that Subaru cannot fix something so simple. Then again, they had head gasket issues for years, and for a time excessive oil consumption issues (as do some other brands in recent years). Sulfonation has nothing to do with it. So I doubt the device added on will help in any way.

 

[Blumlein 88]

https://www.subaruoutback.org/threads/2017-outback-battery-issue-lack-of-starlink-subscription-cause.531683/page-2

Look at post #22 here. I didn't know your 2015 had this system. If like those of other brands, it probably keeps your battery charged only to 80% to get this, increase battery life and save gas. If however your car does not enter sleep mode then it means the car discharges more deeply as the battery is not 100% charged to start with. If not for the sleep issue, it would extend battery life a bit.

 

[notsodeadlizard]

1. Lead acid battery has low internal resistance (less than 0.3 Ohms typically)
2. Of course, battery voltage for in-vehicle electronics is filtered and very well filtered.

So, an explanation for non-engineers is good enough.

 

[Fred H]

Thank you for the comprehensive information, @Blumlein 88. This is more complete than I found on the Subaru forum. I particularly appreciate you correcting your earlier comment.

I just read your last comment and skimmed the thread you linked to. The Outback differs mainly in suspension height and body shape, so the information is particularly welcome. I will read it in detail. Again, thank you.

I will use a battery tender weekly, and the nights before a trip. Even if it doesn't make the battery last longer, I'm more likely to complete planned trips.

 

[Philbo King]

Thank you for the comprehensive information, @Blumlein 88. This is more complete than I found on the Subaru forum. I particularly appreciate you correcting your earlier comment.

I just read your last comment and skimmed the thread you linked to. The Outback differs mainly in suspension height and body shape, so the information is particularly welcome. I will read it in detail. Again, thank you.

I will use a battery tender weekly, and the nights before a trip. Even if it doesn't make the battery last longer, I'm more likely to complete planned trips.

I keep mine plugged in whever the unit is in the garage. Cheap insurance.

 

[pseudoid]

Okay, so I admit I got a geezer car (2006 goat) and the current Optima-Yellowtop should be replaced after 6years in duty.
Searching for my options online, I kept coming across recommendation for replacing it with an AGM battery.
Huh? Wut?

AGM stands for Absorbent Glass Mat and is an advanced type of lead acid battery that is sealed, spill-free, and maintenance-free.

I hope the fact that some are made of "flat plates of 99.99% pure virgin lead" is not a snake oil.
Plot thickens as the older BatteryTenders may even need to be replaced... [developing...]

 

[G|force]

The quality of Optima batteries has steadily decreased over the years, but they are in fact AGM.