Battery maintenance on modern vehicles

Submitted: Friday, Jul 06, 2018 at 12:39
ThreadID: 136945 Views:1695 Replies:9 FollowUps:22
This Thread has been Archived
After having our original 3yo second battery load tested and declared defunct it was pointed out that in the present set up being charged with a Redarc Isolator system, the alternator will only produce maximum 12.7v or 12.8v as my Pajero computerized system is designed to ‘top up’ the main battery then quit – a fuel efficiency built into most modern vehicles. This probably explains past problems.

I thought I could top up the second battery with the smart charger on 240v and achieved 14v after a few hours. Problem solved I reckon (only have to do that now and then whilst travelling and it should retain full capacity for running the Engel.)

Next day I took two 90km runs and checked both batteries again to find they are back to 12.7v (main) and 12.9v (second) with no fridge attached so I have accomplished nothing with the ‘boost charge’.

We are heading north next week, hoping to free camp at various locations and packing 200w panel system for the van batteries, which regulates down to around 13.7v and hope to rely on the second vehicle battery for one of two Engels and am worried the battery will not cope for long with only 12.7v max charging.

Should I be concerned and is there a better plan for the battery life maintenance please?

This trip we will be checking just how long we can stay off the grid with existing gear and assess what adjustments may be required. I plan to have two 105 a/h batteries in the van, the second vehicle battery is a Bosch High Cycle Marine HCM 24-600 M4 provided by Goodchild Ent. in Cockburn. It is 60 or 70 a/h and 600cca. They steered me to this in preference to the Fusion batteries which are stated to be suitable under bonnet, but Goodchild advise ‘not for Aussie conditions’. I respect their stance on that call.

Thanks & cheers - Phil
Phil 'n Jill (WA)

Member
My Profile  Send Message

Back Expand Un-Read 1 Moderator

Reply By: CSeaJay - Friday, Jul 06, 2018 at 12:48

Friday, Jul 06, 2018 at 12:48
Phil

12.7V is the normal "full" or "100% state of charge" on a rested battery.
The 14V you saw would have been whilst charging or shortly thereafter. If you rested that battery you probably would have see 12.7V perhaps a bit more but less that 13V

So what you describe sound s normal to me
AnswerID: 619980

Follow Up By: Member - Phil 'n Jill (WA) - Friday, Jul 06, 2018 at 21:39

Friday, Jul 06, 2018 at 21:39
Thanks for that - I expected it would settle some but not to that extent. normally I would have have done another reading after the charge but I had to get the grandkids off to a bit of entertainment so only half did the job. If the battery can handle it around those figures all is well. I have just started the fridge for an overnight test to see what the outcome will be.
Regards - Phil
Phil 'n Jill (WA)

Member
My Profile  Send Message

0
FollowupID: 892333

Reply By: RMD - Friday, Jul 06, 2018 at 13:09

Friday, Jul 06, 2018 at 13:09
Phil 'n Jill
The redarc is not a charger at all so it isn't charging any battery, simply allowing charge to pass to whatever is connected to it. Only the alternator charges the batteries in that circuit. To me, Charged "via" is different to charged "by".
If the Engel is running off the vehicle aux battery it may be a good idea to have a charge line from your van and it's 2 x 105 ah batteries, so as to connect to the smaller aux battery, which you said is under the bonnet, so it is charged whilst stopped.
Perhaps and anderson plug to van battery connector and a lead to that Engel power source will provide longer stays to be able to run the Engel too with some surety.

If wanting longer stays in one spot, having solar panels and regulator on the van may be a sound idea. It is good to have a portable paneloption though, to maximize sun opportunities.

It would be possible to have the small aux battery and the van batteries connected through anderson plugs and suitable cabling and use a DC/DC unit to charge those three batteries while driving. That way you begin your stay with the batteries fully or near to fully charged when you stop.
AnswerID: 619981

Follow Up By: Member - Phil 'n Jill (WA) - Friday, Jul 06, 2018 at 21:54

Friday, Jul 06, 2018 at 21:54
Thanks RMD - I wasn't very clear about the Redarc - yep it is an 'isolator' - I was really trying to convey it was under charge - with that being attached to keep the two batteries apart - i.e. both charging but one draining separately from the main.

My hopes that one Engel (the smaller unit) can run from one deep cycle battery overnight is purely based on the first Engel I had over thirty years ago, being able to operate off the starter battery in the old Holden without draining it. Maybe I was just lucky or batteries were better back then.

The panels are borrowed from son in law in two sections folding for storage and connected by 10 metres of cable for shifting for max solar benefit. I will be experimenting with charging options this trip before committing totally to solar versus generator, keeping in mind my limited opportunities.

DC/DC yet to be explored.

Cheers - Phil
Phil 'n Jill (WA)

Member
My Profile  Send Message

0
FollowupID: 892335

Reply By: Stevemac - Friday, Jul 06, 2018 at 14:00

Friday, Jul 06, 2018 at 14:00
Wouldn’t one of those voltage boost diodes fix this?

I think Sidewinder does them for $35

AnswerID: 619982

Follow Up By: Alloy c/t - Friday, Jul 06, 2018 at 15:36

Friday, Jul 06, 2018 at 15:36
Yep ,they 'trick' the alternator into that extra .5 of a volt on a 'smart' alternator and is a less that 1 minute fix , does not hurt the standard wet cell starting battery and is almost a requirement to boost the voltage going into an AGM......
0
FollowupID: 892317

Follow Up By: HKB Electronics - Friday, Jul 06, 2018 at 17:22

Friday, Jul 06, 2018 at 17:22
You can't use a booster with ECU controlled alternators.
HKB Electronics

Business Member
My Profile  Send Message

0
FollowupID: 892320

Follow Up By: Member - Phil 'n Jill (WA) - Friday, Jul 06, 2018 at 21:57

Friday, Jul 06, 2018 at 21:57
Thanks guys - that was starting to look good - I contemplated seeking Derek's assistance, but looks like HKB just threw cold water on that & it is understandable - these modern electronics are a law unto themselves.

Cheers - Phil
Phil 'n Jill (WA)

Member
My Profile  Send Message

0
FollowupID: 892336

Follow Up By: Alloy c/t - Saturday, Jul 07, 2018 at 08:48

Saturday, Jul 07, 2018 at 08:48
Then tell me why that in the FJ Cruiser that has an ECU controlled alternator that a diode replacement type fuse supplied by Derek works and works well and has for the last 5 years in conjunction with his simple dual battery isolator ..... charging rates do not lie , the booster increases the voltage by .5 of a volt over all temperature and rev range .....5 years on and still original factory fitted Panasonic starting battery and a Optima yellow top as aux also 5 years old ....
1
FollowupID: 892343

Follow Up By: HKB Electronics - Saturday, Jul 07, 2018 at 09:58

Saturday, Jul 07, 2018 at 09:58
Yes booster work well with the FJ cruiser, I have been supplying them to many here, the US and other parts of the world for years. The reason they work in the FJ cruiser is that it doesn't have an ECU controlled alternator.
HKB Electronics

Business Member
My Profile  Send Message

1
FollowupID: 892344

Reply By: HKB Electronics - Friday, Jul 06, 2018 at 14:07

Friday, Jul 06, 2018 at 14:07
IF your car does have an ECU controlled alternator then you really need a DCDC charger under bonnet to look after the car aux and a DCDC in the van for the van batteries.
HKB Electronics

Business Member
My Profile  Send Message

AnswerID: 619983

Reply By: Gazza70 - Friday, Jul 06, 2018 at 17:01

Friday, Jul 06, 2018 at 17:01
Hi Phil,

I would be a little concerned on the life span of a 60 / 70 amp battery running an Engel fridge particularly in warm conditions. Remembering the rule of thumb to preferable not discharge to more then 50% of amp capacity.

Guess it should be okay if you are regularly on the move or hooking up a panel to it when camped up.

I have a dedicated 120amp to run my 50litre Waeco CFX, used as a fridge only.

Regards Gary
AnswerID: 619990

Follow Up By: Member - Phil 'n Jill (WA) - Friday, Jul 06, 2018 at 22:02

Friday, Jul 06, 2018 at 22:02
Thanks Gary

I guess it is a punt but only experience will produce the answer to this I guess. I'm not sre it is worth carting around the second battery if it can't handle the fridge overnight.

If it was only hooked up whilst travelling it wouldn't be necessary, the main battery could cope. The Engel is half the size of yours so let's hope it has half the draw.

Cheers - Phil
Phil 'n Jill (WA)

Member
My Profile  Send Message

0
FollowupID: 892337

Reply By: 2517. - Friday, Jul 06, 2018 at 17:52

Friday, Jul 06, 2018 at 17:52
What I have seen done to Pajeros they fit a 100 amp battery in the front of the battery box to be used as auxiliary,then a Opitma battery as starter battery at the back then extend the leads. This way you have a 100 amp auxiliary.
AnswerID: 619996

Follow Up By: patsproule - Friday, Jul 06, 2018 at 19:43

Friday, Jul 06, 2018 at 19:43
Yep. I have a 2016 NX. With a bit of plastic cutting the front tray will hold a 100AH NZ70 battery. A slightly smaller tray sits behind across the firewall holding the original factory starter. I then have a Projecta DC to DC on the firewall for charging duties. This has no problems with the smart alternator.

In the previous NP I had the same battery setup with an Optima red top as the crank (awesome battery that lasted more than 5 years). But I had an old school VSR setup. It used to destroy an aux battery every 2 years or less - usually through excessive gassing. In my opinion the DC/DC charger is well worth the investment.

Pat
0
FollowupID: 892323

Follow Up By: RMD - Friday, Jul 06, 2018 at 21:16

Friday, Jul 06, 2018 at 21:16
patsproule
Having any DC/DC unit on the firewall means it is heated by the engine and engine bay heat. Usually that will cause the DC unit to degrate it’s ouptput because it generates it’s own internal heat anyway and adding heat above what it creates will cause it to limit it’s output.

A DC/DC unit can’t possibly work at full output under those circumstances. It will be running heat stressed most of the time instead of as cool as possible.

Because it is a switchmode device that situation has to shorten the life of the DC/DC unit. Running electrolytic capacitors quite hot isn’t a recipe for long life.
0
FollowupID: 892332

Follow Up By: Zippo - Friday, Jul 06, 2018 at 21:48

Friday, Jul 06, 2018 at 21:48
Yep, with so-called "smart' alternators (i.e. ECU controlled) a DC-DC-charger is necessary to ensure the auxiliary battery is properly charged. The recommended types are ignition-controlled rather than voltage sensing, as the latter type have trouble with the low cranking battery voltages after the ECU turns down the wick.

The best place for a DC-DC charger is (a) away from external heating (such as under-bonnet) and (b) close to the battery it is charging.
0
FollowupID: 892334

Follow Up By: Member - Phil 'n Jill (WA) - Friday, Jul 06, 2018 at 22:09

Friday, Jul 06, 2018 at 22:09
Thanks fellas - the swapping batteries around is thinking outside the square - great idea.

Having made the investment at this stage I have to bite the bullet and see how this lot works out.

The other comments are taken on notice and extremely helpful - as usual.

I will endeavour to provide an update of how this all pans out at some point when I have been able to offer some feedback.

Planning to work our way back to Wyndham where the climate is a bit warmer at this time of the year.

Cheers all

Regards - Phil
Phil 'n Jill (WA)

Member
My Profile  Send Message

0
FollowupID: 892338

Reply By: Member - Phil 'n Jill (WA) - Saturday, Jul 07, 2018 at 18:47

Saturday, Jul 07, 2018 at 18:47
Just an update on the overnight exercise - the Smaller Engel was chilled on 240v with a 10 litre water container stowed then switched to the new battery, which read prior to connection at 6.45pm as 12.75v.
First readig at 83.0pm - 12.55v Bit worried at this point.
10 pm reading 12.6v - relieved.
2.00 am reading - still 12.6v - starting to relax.
8.00 am reading - 12.5v - & rather pleased at the outcome.

Overnight our temps were very coolish and the frig probably only ran on the odd occasion - setting was on 2 - (around beer setting on my older unit) - hoping this is the same (borrowed from father in law)

Googled specs for this Engel MRFT 525D-M4 and amps draw shown as - 0.5- 3.3 amp.

The specs plate on my old unit has been scratched and being either 40 or 45 litre, the readings will be higher I guess - only one way to find out - another experiment overnight.

The plan is to use this unit as a freezer for the trip, running it from the main battery on cig lighter socket whilst travelling. Powering off the van batteries whilst parked. This also allows me to keep a few freezer blankets to share between units which I have found very efficient in reducing the power draw on past trips - but mostly whilst on the move.

Thanks to all respondents.

Cheers - Phil
Phil 'n Jill (WA)

Member
My Profile  Send Message

AnswerID: 620028

Follow Up By: Member - McLaren3030 - Sunday, Jul 08, 2018 at 12:48

Sunday, Jul 08, 2018 at 12:48
Hi Phil ‘n Jill, better off with a hard wired seperate “merit” type plug, rather than a normal cig. Lighter plug. Less chance of voltage drop or excess heat.

Macca.
Macca.

Lifetime Member
My Profile  My Position  Send Message

0
FollowupID: 892363

Follow Up By: HKB Electronics - Sunday, Jul 08, 2018 at 13:30

Sunday, Jul 08, 2018 at 13:30
Interesting you write that McLaren3030, I have had just as much trouble with merit
plugs as I have had with cig plugs over the years. These days only use Anderson plugs for fridges, compressors etc.
HKB Electronics

Business Member
My Profile  Send Message

0
FollowupID: 892365

Follow Up By: Member - Phil 'n Jill (WA) - Sunday, Jul 08, 2018 at 14:33

Sunday, Jul 08, 2018 at 14:33
Thanks again fellows.

I have actually a dedicated line installed for the bigger Engel and appropriate 2 pin socket,but this smaller unit was a last minute addition and I will have to chance it for now. I think this is the smallest of the Engels so we might get lucky - otherwise I will be visiting a workshop in Exmouth I reckon.

The big Engel overnight pulled the 2nd battery down from 12.6v (bit low starting point) to 12.17v - which I assess as 50% drawn by the chart I picked up here on EO.

I am going to be paying a lot more attention to both batteries this trip, after having one 'non-start' day last year at Exmouth - fortunately at the caravan park with plenty of support around. That was when I found the 2nd battery was on the way out because I couldn't jump off that as was my long held belief. It has now been replaced for this trip.

Regards - Phil
Phil 'n Jill (WA)

Member
My Profile  Send Message

0
FollowupID: 892367

Follow Up By: Member - McLaren3030 - Monday, Jul 09, 2018 at 13:16

Monday, Jul 09, 2018 at 13:16
Hi HKB Electronics, strange that, as I have read several articles on the merits (pardon the pun) of cig. lighter plugs vs Merit plugs, and every article recommends Merit over Cig. Lighter plug. However, I agree that an appropriately sized & wired "Anderson" type plug is the better option. My 60 Ltr. Engel is plugged in with the dedicated 2 pin Engel plug & socket wired to the Deep Cycle Battery.

Macca.
Macca.

Lifetime Member
My Profile  My Position  Send Message

0
FollowupID: 892374

Reply By: Member - DingoBlue(WA) - Tuesday, Jul 10, 2018 at 15:32

Tuesday, Jul 10, 2018 at 15:32
Hi Phil 'n' Jill
Just a quick note on my recent trip to Coolgardie. I run the two batteries in my 105 Landcruiser with a Redarc isolater and a 100A/hr in the camper trailer connected to the vehicle via an Anderson plug.
My batteries in the vehicle generally charge at 14.2 volts.
I have 40 lt. Engels in both the car and camper trailer running at 4 deg.
I arrived in Coolgardie on Sunday evening and left on Wednesday morning. Both fridges were running continuously over that time. The battery in the camper trailer operated the water pumps, lights and winch which still folded up the camper on Wednesday morning with no problems.
The car was fine as the cranking battery was isolated.
I didn't check the voltage of any of the batteries so cannot advise the drain, however, it appears that you can get 2-3 days without charging.
I carry a solar panel and gen set for extended stays or overcast conditions.
Trust this info is of assistance.
Rather a bottle in front of me than a frontal lobotomy!

Lifetime Member
My Profile  My Blog  Send Message

AnswerID: 620074

Follow Up By: Member - Phil 'n Jill (WA) - Tuesday, Jul 10, 2018 at 22:29

Tuesday, Jul 10, 2018 at 22:29
Thanks DingoBlue - I am envious - firstly in the charge rate you achieve of 14v plus and then running the camp for a couple of days no problem. Hope I fare as well next week.

Just curious - you don't have any other gear assisting at all - like the DC-DC chargers mentioned in this thread? (which still remain a mystery to me as I haven't researched them yet.)

Sounds an ideal arrangement most of us would be pleased to have.

Thanks again - happy travelling

Regards - Phil
Phil 'n Jill (WA)

Member
My Profile  Send Message

0
FollowupID: 892400

Follow Up By: Member - DingoBlue(WA) - Tuesday, Jul 10, 2018 at 23:28

Tuesday, Jul 10, 2018 at 23:28
Hi Phil,
I don't know what a DC to DC charger is either. (and I don't really care to know) There are a plethora of gadgets available these days but my philosophy is to keep it simple, less things to go wrong.
I just usually keep an eye on the fridge temperatures which will indicate if the battery is getting down a bit.
Rather a bottle in front of me than a frontal lobotomy!

Lifetime Member
My Profile  My Blog  Send Message

0
FollowupID: 892401

Follow Up By: Member - Phil 'n Jill (WA) - Tuesday, Jul 10, 2018 at 23:39

Tuesday, Jul 10, 2018 at 23:39
Fair enough - the old 'KISS' method - can't get much simpler than that.

My fridges are too old for temp readings but I have mastered the one task on the multimeter to check their status - but I have to get off my butt to do that.

Cheers & thanks for the feedback

Regards - Phil
Phil 'n Jill (WA)

Member
My Profile  Send Message

0
FollowupID: 892402

Follow Up By: Member - DingoBlue(WA) - Tuesday, Jul 10, 2018 at 23:45

Tuesday, Jul 10, 2018 at 23:45
I bought the $700.00 Engels which don't have a temp guage. about $300.00 cheaper than the ones with a digital guage. I bought two temp guages from Jaycar at about @15.00 each and just stick the probe inside the fridge. The reader is magnetic so easy to attach nearby. I remove the batteries when not using and just clip them in when I'm going away.
Rather a bottle in front of me than a frontal lobotomy!

Lifetime Member
My Profile  My Blog  Send Message

0
FollowupID: 892403

Follow Up By: Member - Phil 'n Jill (WA) - Tuesday, Jul 10, 2018 at 23:55

Tuesday, Jul 10, 2018 at 23:55
You got a steal of a deal at that price. I have seen some fairly similar offers around Xmas last year, but I can't complain about the old units whilst they still keep the beer cold.

I will check the gauges at Jaycar, they are starting to know me well after the past week - I bit the bullet and bought their 160 watt solar pack when I was having trouble hooking up the son in law's unit to my setup & hesitated to start modifying his gear to this trip.

Regards - Phil
Phil 'n Jill (WA)

Member
My Profile  Send Message

0
FollowupID: 892404

Reply By: nickb - Friday, Jul 13, 2018 at 00:22

Friday, Jul 13, 2018 at 00:22
My Ford Ranger has an ECU controller alternator but a Ford dealer can change the computer setting to “dual battery mode” (or similar). Then the alternator works like an old style one that just puts out a constant 14.6V.

Is that something that you can ask the dealer about?
AnswerID: 620116

Follow Up By: Member - Phil 'n Jill (WA) - Friday, Jul 13, 2018 at 10:14

Friday, Jul 13, 2018 at 10:14
Good question Nickb - thanks for the tip.

I will check with the gurus on Pajero forum.

Simple solution indeed.

Cheers - regards -Phil
Phil 'n Jill (WA)

Member
My Profile  Send Message

0
FollowupID: 892450

Popular Content

Popular Products (14)