12v Fridge vs Esky & different ice blocks

I have a 100lt fridge/freezer in my Trayon. It only draws about 2ah and is excellent. However, when storing fresh vegetables , fruit , milk, beers, etc., the fridge can get full quite easily. I now tend to run the fridge on high to freeze everything. I have a cooler box which I keep cool with bricks frozen in the fridge and rotate them through the cooler to look after perishables and keep drinks cool (if not cold!). This works very well and I can store the cooler out in the annexe to free up room inside. As the 'frozen' food (generally just below -1 deg) in the fridge part) is used up, I can back off the fridge and move stuff from the cooler. Using both systems in tandem is great for extended trips.
Another huge benefit is a cryovac system. Vac sealed food lasts for weeks, if done properly. I prepare a lot of meals/food at home for her indoors, then vac seal and freeze the leftovers. They make a convenient meal because I just heat them in some simmering water, cut the bag and slide onto the plate.
Job done!

Another one for the Vacuum sealer. We purchase meat and some veges then vacuum pack them and keep them in the Engel at 3 Deg c . Meat lasts up to 5 weeks like this and veges a bit longer however you will eat them out well before 5 weeks .

Some of what you say is true, but you dont "need" fancy electronics.
If you stick with a flooded type battery you dont need any electronics at all, just the battery, fridge and a cheap panel that has an on board reg. There are plenty of people doing it that way.
It is forums that insist that what people do successfully cant possibly work. Many myths come from forums invented by confused authers thinking they know what they are talking about but misunderstood what they read on google written by uneducated people. There are also books available by self proclaimed experts that didnt own their own multimeter till they retired and set up their first travelling rig.
By the way, this little rant is not directed at anyone in this forum.

As someone who has just purchased a fridge for travel (when we're allowed to), and who is contemplating the cost of the fancy electronics, I'd be interested in any guidance about where to find more information about the sort of budget approaches to powering a fridge when stationary mentioned by qldcamper.

Interesting question.
Most info available leads you to believe you have to have everything conceivable or it wont work.
I run 2 seperate systems, my camper is simply a battery and a cheap solar panel through a victron reg, pretty simple.
The one in the car is a bit more complex.

Just do the math on how much power you need for the way you use your fridge and size the battery and solar accordingly, if you even need solar.

.
Hi Briste,

Further to Qldcamper's advice, if you could advise answers to the following questions we can probably offer informed advice........

1) What is your vehicle and will the fridge be in the vehicle or in a towed camper or caravan?
2) What else is to be powered other than the fridge? e.g. lights etc.
3) What size is the fridge and will children use it for drinks?
4) Will you be storing frozen food in the fridge?
5) How long will the vehicle be stationary? e.g. overnight, a full day plus night, or more?

As Qldcamper has said, well specified simple systems can usually provide adequate performance in most cases. However, there are constraints and you need to be aware and accept them to avoid disappointment.

Briste.
As an example of simple stuff, For many years I used a 12v, manually switched ON solenoid, ie, constant duty, to connect some reasonably heavy wiring to an aux battery. Therefore it was charged from the alternator. The fridge ran off the aux battery.
If I wanted the aux battery charged I switched on the solenoid. It can be made to auto connect and disconnect by running the solenoid coil feed from IGN source.
Rules change in todays world. Unfortunately, if your vehicle has a modern Dumb, some call them Smart alternator, it may be best to have automatic charging of the Aux via a DC DC charger which is initiated by Ign sensing. Either install a Volt meter, Small Digital) on the Aux battery or regularly/daily use a multi meter to monitor the battery voltage as fridge is used.
Off camping now!

Thanks for those replies. Answers to Alan's questions, with a bit of context:

1) Toyota Prado Kakadu 2021 model. The fridge will be in the back of the Prado, rather than in the hybrid off-road van that I will be sometimes towing. The fridge is intended to compliment the smallish fridge freezer in the van. It may also be used for trips without the van.

[Context: the Kakadu is payload-challenged, esp when towing, so I am doing all I can to work with that payload. I therefore have a strong preference for anything light such as a lithium battery. They're definitely not cheap, but have a number of advantages in addition to being light.]

2) I only really plan to power the fridge. No inverter. I guess if it was possible to add some 12V charging outlets for as-yet-unknown low current bits and pieces without adding to the cost too much then I'd tick that option.

3) Bushman SC 35-52. No children planned on any trips. The Kakudu has a chilled centre console - I haven't used this feature yet, but it seems the obvious place for frequently-accessed cool drinks when travelling.

4) Sometimes as a 35L fridge, sometimes as a 35L freezer, and sometimes as a 52L multi-zone fridge freezer.

[Context: We discussed this fridge recently in a separate thread, much to the amusement of some people. Can I suggest we leave the discussion about the wisdom or otherwise of that multi-zone approach to that other thread. I'm experimenting with it at present, and will report back at some stage. I'd rather the discussion here be focused on powering the fridge.

Speaking of which, there was some discussion in that other thread about whether the Bushman really is as economical to run as some people claim. The Choice review of camping fridges found that the Bushman was the most economical to run. HOWEVER ... despite Choice's attempts to make comparable measurements, it wasn't really a fair fight. They only ran it in 35L fridge mode, and the Waeco Dometic CFX50W 50L was close behind. On an amps per litre basis the Waeco would be ahead. The reality was that both these units were close and *way* ahead of the rest, notably the Engel MT45FP 40L. They both seem quite economical to run.]

The obvious, and expensive, solution seems to install a lithium battery in the back with the fridge and hook up all the basic Redarc gear required to charge the battery from the car when possible, and via solar at other times. I guess I was attracted to the alternative of a system not charged by the car. I assume it would be cheaper, and more flexible. I.e. you could remove and run it outside the car, although that really isn't a priority. I was attracted by price and simplicity.

5) I'd like plan for being stationary and off-grid for 3-4 days, occasionally.

"5) I'd like plan for being stationary and off-grid for 3-4 days, occasionally."

My fridge is a 55 litre $600 (12 years ago) Chinese no-name that refuses to die. It draws 2.5 amps when running. I usually use it as a minus 10 freezer when camped. (It has a chiller compartment for non frozen items.)

I have 120Ah AGM (would like lithium, but the AGM was a warranty job so I had to take it), a mid range PWM solar controller and 200 watts of solar in 2 light weight, portable, thin panels so I can run one if the sun is good, 2 in parallel if not so good.

As long as there is reasonable sun, my system keeps up with the fridge for as long as I want to stay.

For a more economical solution and one that doesn’t impede on your storage space you could consider a AGM dual battery under the bonnet. You could compliment that with a solar blanket when needed

A very simple and cost effective solution

.
Briste,

Thanks for those excellent answers. So often people offer assistance only to find they were not fully informed.

I believe the Prado to have a temperature-controlled alternator but it is not 'voltage-regulated' (smart) so it is suitable to charge an auxiliary battery without needing a dc-dc charger. Just use a voltage-sensing solenoid. Redarc is good but there are cheaper ones.

A lithium battery would be nice although expensive and would desirably require an appropriate charger although people some have stated that they have connected directly. I would not wish to risk the investment. A 100Ah battery should be adequate for your fridge load and would also handle phone charging and modest LED lighting.

A 120W solar panel would sustain your fridge for most of the time and you can also use the engine to charge on occasions when the solar is inadequate. A "solar-only system" would likely need more than 120W and having it removable from the car could be messy.

Frank's answer above is reassuring but does incorporate extra solar panels for "those days".
And Alby's idea of putting a battery under the bonnet affords less intrusion into the cab. It would be wise though to use a battery that will withstand heat.

Other members may provide more good advice and feel free to ask more questions.

Hi Briste, and for anyone else who may be interested,

My set up for the back of my wagon is a 60 Ltr. Engel fridge/freezer, a 100 amp LiFePo4 battery in the right wing and a Redarc 1240 dc/dc charger in the left wing of my drawer system. The Redarc is powered from the cars alternator when driving, and from a 200 watt folding solar blanket when stationary. Solar blanket is connected via an Anderson plug on the back of the car. The fridge is used mainly for drinks and as an overflow for the van fridge.

Only reason we have a 60 Ltr. Fridge is that it is 18 years old and purchased long before we had a caravan, so this was our only fridge at the time. When travelling it is at least 3/4 full with drinks, and then whatever else we cannot fit in the van fridge. If we were setting the car up from scratch now, we would probably only buy a 40 Ltr. Fridge.




Macca

Thank you for those excellent responses. There's a lot of useful information there to consider and pointers for further research, which is what I asked for.

I'm not sure whether people realise just how payload-challenged the Prado Kakadu is in practice, despite what the varying Toyota spec sheets say. I took the new car over the local public weighbridge with a full tank and found only a payload of 510kg, + or - given the weighbridge accuracy. Put two slightly overweight people in there, add an estimated 180kg towball weight (based on measuring an identically-specified, loaded model), and I've not got all that much left. I would like to have the capacity for light-weight front bar. The rear seats are coming out, which should save 40-50kg, but I've bought a 24kg fridge plus an extension pack. There's going to be plenty of spare cargo space in the Kakadu - so the battery would not be that much of an imposition on space - but not a lot of spare payload. The van will be the opposite - spare payload but not much spare space. Some may say that the Kakadu wasn't the best choice for towing, and there's *some* truth to that, but it is what we have, and so the question is how to make it work?

Thus why I would strongly prefer a lithium. I've dropped the coin on the Kakadu, and the cost of that choice may well be dropping a bit more on the second battery choice, and that may require yet more coin on "fancy electronics". If I had the spare payload I may well put an AGM the engine bay in the spot intended for one, but that extra weight may well be the difference between having a front bar or not.

My reading of the responses seems to suggest that lithium would be difficult / risky to do without a connection to the vehicle, and thus hard to make portable. I've got that right?

@Frank_P: you find that you need your fridge left over from the Cultural Revolution in the back of the tug to compliment the capacity of the fridge in your early model KK? I.e. that it's difficult to survive on just that KK fridge?

Hey Briste,

The Long March fridge was bought when we had a camper trailer. As I said, it won't die - so why not use it? When we're towing the KK that fridge is all minus 19 freezer and along with the KK fridge allows us to be where we like to be for longer - away from the masses. (Actually -19 when driving and the fridge running off the alternator, -10 when camped up and running off the KK.)

But the KK is not always with the tug. I like to rough it occasionally, Mrs P not so keen. So the tug is fitted out for solo camping and part of that was including the already-owned People's Revolutionary Fridge.

The power scenario I gave above was my solo camping setup.

When the KK is with us those little solar panels don't get used - the KK with its oodles of power and solar runs everything.

Briste,

The 100 amp LiFePo4 battery in the back of my wagon (LC200) only weighs around 14 Kgs from memory. You don’t need fancy “electronics”, but you do need a suitable dc/dc charger with a LiFePo4 profile. All up weight would be less than 18 Kgs. A folding solar blanket would weigh less than folding solar panels, and take up less room. Renogy & Solar King seem to be the most cost efficient quality LiFePo4 batteries, check them out on line. I would steer clear of the cheap Chinese batteries for now.

ITech have a LiFePo4 battery they say is suitable for in the engine bay, but if putting any battery under the bonnet, I would certainly ensure there is plenty of heat protection around the battery.

Macca.

.
Hi Briste,
I think that I can see where your heading.

You certainly could put a 100Ah lithium in the back of the Prado together with a dc-dc charger with solar input. I would however select quality products rather than cheapest. For my new motorhome I have used Enerdrive throughout. Redarc are good quality but Enerdrive offer more value.
So I suggest:
Battery: Enerdrive 100Ah E-lite at $870
Charger: Enerdrive EN3DC40A at $445 (Redarc 25A is $450)
The advantage of a 40A charger is that the lithium will easily accept the higher current and faster charge from the alternator. Useful if you need to recover from overcast conditions.

I cannot see where you gained..... "lithium would be difficult / risky to do without a connection to the vehicle, and thus hard to make portable."
I see no reason why you could not configure the system with Anderson plugs such as to simply lift the battery and fridge out of the vehicle and connect to portable solar panels. If you went that path you could opt for a cheaper charger sans solar input for when the battery is in the car. The solar can still be connected directly to the battery via its regulator.

Those are some mighty useful responses. Thanks to all. I'm off to digest them.

@Allan B: Where I got that "difficult / risky" comment was from a misinterpretation of your statement "A lithium battery would be nice although expensive and would desirably require an appropriate charger although people some have stated that they have connected directly. I would not wish to risk the investment", so thanks for that clarification.

@Frank_P : my impression from inspecting a few KKs was that the fridge space wasn't too bad but the freezer space was quite limited, and so more freezer space is needed. But if you're travelling in warmer climes, and want to carry plenty of salad vegetables along with the usual fridge contents, you can run out of fridge space pretty fast. Hence my interest in something that could be run as dual zone if nec.

"@Frank_P : my impression from inspecting a few KKs was that the fridge space wasn't too bad but the freezer space was quite limited, and so more freezer space is needed. But if you're travelling in warmer climes, and want to carry plenty of salad vegetables along with the usual fridge contents, you can run out of fridge space pretty fast. Hence my interest in something that could be run as dual zone if nec."

Yes, the KK fridge is limited. We effectively get our dual zone by running the car fridge as a freezer and using the KK fridge as, well, a fridge. That freezer compartment in the KK fridge is handy for making ice blocks for the G&T and Scotch :-) and a few bits and pieces that you might want to keep a bit cold, but its real purpose is just to "generate cold" for the rest of the cabinet for stuff you want to keep fresh but not frozen.

The Peoples Revolutionary Fridge (PRF) is not a real dual zone. It has one proper, large compartment with a wrap-around evaporator and alongside that a comparatively small compartment that is cooled by spill-over from the main, adjustable with a slide that controls the amount of spill-over.

When solo camping, I run it at minus 10 with the main compartment half to three quarters filled with pre-frozen stuff which stays frozen for days. I use a beach towel folded into a thick insulator on top of that frozen stuff then on top of the insulator I put my coldies and other stuff that I want really cold but not frozen - with normal use taking cold drinks out and putting warm replacements back in that top layer doesn't freeze. Other stuff that might suffer from too much cold goes into the small compartment that under my system doesn't freeze.

It sounds dodgy but it works, has done for years.

And the microwave for thawing frozen stuff? It's the 3.2 litre 5 cylinder 138kW model. A frozen steak placed on the heat shield above the turbo some time after arriving at camp is thawed perfectly in a couple of hours :-)

@Frank_P: Re "When the KK is with us those little solar panels don't get used - the KK with its oodles of power and solar runs everything."

Can I just clarify how you're powering The-East-is-Red-Fridge from the KK? And is this with the fridge in the back of the tug, or are you removing it?

"Can I just clarify how you're powering The-East-is-Red-Fridge from the KK? And is this with the fridge in the back of the tug, or are you removing it?"

Hi Briste,

It's not very sophisticated, I'm afraid, but certainly meets the KISS principle.

If you are familiar with the Kimberley Karavan you will be aware of the front "Multibox" on the A frame, where the batteries reside. My solar regulator is in there with the batteries. The regulator has a Load outlet to which I have wired an Anderson plug.

I've made up a suitable cable and when we're camped up I run the cable from the regulator's Load plug to the PRC Red Army fridge in the tug's canopy where I swap the fridge's power lead from its socket in the ute's power board to the cable. The fridge stays in the canopy where I keep it ventilated and shaded.



Cheers

Thanks Frank. I was forgetting that your tug was a ute with Canopy. Harder to leave the fridge wired like that in a wagon, but not impossible. I guess an external anderson plug could be installed, wired to the fridge.

@Alan_B: are you in a position to indicate your source for the pricing of the Enerdrive gear, esp the battery? Pity the slimline models are so expensive.

.
Yeah, sure Briste. Enerdrive do not sell direct, only through dealers.
I got all my Enerdrive stuff from Caravan RV Camping. I have found them to be a good supplier.

Incidentally, Enerdrive was acquired by Dometic in May of this year, which perhaps says good things about Enerdrive products.

@Alan_B: Was there anything other than price behind your recommendation above for the e-LITE rather than the similarly spec'ed B-TEC? As I understand it, they're the same technology, but the B-TEC has a wireless monitoring module and is serviceable. Asking that question another way, in your view are these features worth the extra, which is considerable? Are you using an e-LITE in your new motorhome, and if so what are you using for monitoring?

(I'm seriously considering a Baintech slimline lithium, as they're only 50mm thick, and thus easy to fit in a range of places, vs 109mm for the B-TEC slimline. But the Baintech, like the e-LITE, requires external monitoring).

.
Briste,
I actually have a Enerdrive B-TEC 200Ah. It formed part of a package deal so I had no reason to consider the eLITE battery.
As you say, both of these are the same battery but the B-TEC incorporates a wireless monitoring direct from the battery to a phone at, of course, a premium price. I have fired up my phone monitoring and found it interesting but my installation includes the comprehensive Simarine monitoring/alarming system so the phone app is rather redundant. I am not one for what I consider 'gimmicky' devices. My system is designed to perform without my supervision. Should something be going South then an alarm will alert my attention. That is how I like things to work and how I designed systems in my time in the instrumentation industry.
However, there is nothing 'wrong' with supervising via a phone app and it may sit more comfortably with some. The only reason why I suggested the eLITE battery was because I thought you were placing economy high on your preferences.

I have no experience with Baintech lithium batteries but they are a reputable company and I have used other of their products with satisfaction.

Briste,

Check out Renogy or Solar King LiFePo4 batteries, you can get 100 amp batteries for around $700. From the reviews I have read, they aseem to be as good as the more expensive brands.

Macca.

I hope it's alright to ask a few follow-up questions before this thread gets too old.

First let me say that reading the above again I can see how I created the impression that I was on a tight budget. It's more that, having dropped a lot of coin already on a touring set-up, I want to be certain that anything additional I spend represents value and is useful. If it is then well good, but I don't want to buy items or levels of quality more than is necessary.

(i) Batteries like Baintech and e-LITE don't come with built-in monitoring. Are there any tips for a useful, value-for-money monitoring system for batteries such as these? I'd like something that enables a quick visual readout. Bluetooth is a possible option but not essential. Some of the Victron battery monitors look interesting.

(ii) @Frank_P: If you always travelled with the KK, do you think it's a viable option to travel without a battery in the tug? What concerns me is powering the fridge when the van is left and side-trips undertaken. Transferring the fridge between the tug and van could become tiresome if done too often.

"(ii) @Frank_P: If you always travelled with the KK, do you think it's a viable option to travel without a battery in the tug? What concerns me is powering the fridge when the van is left and side-trips undertaken. Transferring the fridge between the tug and van could become tiresome if done too often."

Briste,

For our setup and style of travelling, no.

We want to keep the fridge in the car. That model BT50 and its twin, the PX1 Ford Ranger, are renowned for being hard on the crank battery. There is no way I would do without a second battery and run the fridge off the cranker. The risk is too high - even for side trips of a day or two. It would take only one little mishap to end up with a flat cranker with possibly no help in a reasonable time.

What should be barely an inconvenience if there was a second battery could, without it, turn into an unnecessary recovery effort involving emergency services.

If ever our tastes change and we want to travel on the road more travelled and stay in or near more populated venues then perhaps the picture would be different, but as it is we like to be away from crowds, self sufficient and self reliant, so for us a second battery is essential.

PS: I suppose that if we never left the KK behind we could do without a second battery. There is enough juice in the KK and I have configured it and the tug so that if necessary I can run the car and its fridge off the KK's battery. In fact I did that once with my previous tug when its alternator failed. We were 6 hours drive from anywhere. I fed power forward to the tug from the KK and drove home with lights, wipers and aircon for de-misting. The further backup was that if necessary I would strap the Honda genny onto the KK's firewood rack and run that to power the 40amp mains charger in the KK to keep the KK batteries alive. It wasn't necessary, but was there if needed.

This series of follow-ups is getting a bit long, and probably hard to engage with, but I was still hoping to get some responses to qu (i) in my previous post about any recommendations for a useful, value-for-money monitoring system for a LiFePO4 battery in the back of the tug. I assume most people have something for monitoring their battery?

.
Hi Briste,

That is a very open question and could attract a host of unacceptable responses. It all depends on what you consider "useful", and "value-for-money".
What do you want to monitor? It can be as simple as just voltage or as comprehensive as everything imaginable about your battery.
How much "value" do you expect for how much "money".
You are perhaps expecting everyone to take the trouble to nominate their preferences then interrogate them?

Why not simply Google "12v battery monitors" and appraise the offerings for yourself?
If you then want opinions on any that are attractive you could ask the Forum in a new thread.
You have expressed an interest in Victron monitors. Yes, they are good quality. You be the judge of price.

This is offered as a helpful suggestion, not as a criticism.

Briste,

The simplest, cheapest battery monitors display only battery voltage. That may work to an extent for lead-acid batteries, but are pretty useless for lithium owing to lithium batteries' flat discharge profile where the voltage doesn't change much as the battery discharges.

The next best thing, and it need not be expensive, is a coulomb counter. This device monitors current going into and out of the battery and, given a starting point of known Ah capacity of the battery, gives a running total. I have a cheapie that shows current being drawn or charged, voltage, Ah remaining, % SOC and time remaining to full charge if charging. Chinese, $50.00. You'll find them on eBay.

Baintech is a reputable Aussie seller of similar products.

Bear in mind, these simple devices are NOT battery management systems. They won't protect against over charge or over discharge. But they will give you a reasonably accurate indication of the SOC of your battery.

I wanted to reassure people that I had done a lot of Googling of battery monitors (not talking about battery management) before asking my question, and having been around the mulberry bush several times I ended up more than a little confused.

The thing I found particularly confusing was shunts. Using Victron as a commonly-sold example brand example, it seems possible to monitor using just a smart shunt, or with a gauge and shunt, and there's also a version with both a gauge and bluetooth. Is a shunt always needed? Where do they fit into the picture? And where do you install them? It looks like and odd thing to have installed naked in the back of a tug if that's where you've located your lithium battery etc. Following on from Frank's point, are these examples lithium compatible? I assume so, as Baintech sells them, but I can't see anything in the specs that says so.

A number of people in this thread were kind enough to tell me what battery and charger gear they're using, which was very helpful. If they could also mention what they're using for monitoring, that would give me some reference points to assess the range of diverse options that are out there. Hence why I asked here. I thought it better to keep the connection with the above discussion, but every forum is different and I'm happy to take advice on the local custom about when to start a new thread.

.
Briste, a basic shunt is part of the current measuring loop. It is nothing more than a very low value of resistance that is beefy enough to carry a large current. As the current flows through the shunt a small voltage is developed. This voltage accurately represents the rate of current and is fed to the measuring instrument.
It can be left "naked" because it is normally installed in the main negative lead from the battery and as such is not considered "live". So you will usually find them close to the battery.
A "smart shunt" incorporates some fancy electronics that can supply data to other devices or readout instruments. A shunt is needed if your monitor cannot directly accept the large currents involved.

Enough.... I'v been called for dinner.

Briste,

"The thing I found particularly confusing was shunts. Using Victron as a commonly-sold example brand example, it seems possible to monitor using just a smart shunt, or with a gauge and shunt, and there's also a version with both a gauge and bluetooth. Is a shunt always needed? "

If you want a coulomb counter to monitor current into and out of your battery and the SOC, yes.

"Where do they fit into the picture? And where do you install them? It looks like and odd thing to have installed naked in the back of a tug if that's where you've located your lithium battery etc. "

Allan has answered that.

"Following on from Frank's point, are these examples lithium compatible? I assume so, as Baintech sells them, but I can't see anything in the specs that says so."

A coulomb counter doesn't care about battery chemistry. It will work on any battery.

Cheers

Hi Briste,

“Simarine” make a battery monitoring system that has both its own display, and an app that you can monitor from your phone/tablet. They are expandable so that you can monitor not only battery systems, but also water tanks as well. Each monitoring system has its own shunt, that is, there is a shunt to monitor battery inputs and outputs including solar, and another shunt for water tanks and so on. The unit is not cheap, I recently had one installed in my van to monitor batteries and water tanks, all up including labour, I think it was around $2,000. I think the battery monitor on its own was around $800 mark. These numbers are from memory, so might not be quite accurate. Look up Simarine on line.

Macca.

.
Hi Macca, that is what I have installed in the new motorhome..... Simarine with Pico display screen. Everything available on a one touch screen..... All battery and solar info, tank levels, temperatures, alarms. My system runs itself without intrusion but all info is available at a touch if wanted. But as you say, expensive!
It even shows barometric pressure!! Well, it is designed primarily for marine applications. With that and outside temperature, you can decide whether to go out for a hike or stay in with a book! lol

EDIT: Just noted that Caravan-RV-Camping are currently offering a Simarine system as discussed with 300A battery shunt, Quad shunt 4 circuit, voltage/tank module and even an inclinometer (wow) for $1229.

I hadn't forgotten Allan_B's earlier mention of the Simarine monitor. It looks pretty impressive, but it seemed like overkill for monitoring a second battery in the back of a tug, rather than for a motorhome or van install.

Is there another term in common usage for a coulomb counter? I went trawling through all the available monitors, and the only mention I could find was for the Amptron, which is described as a "coulometer". Can you identify one from its funtionality rather than that description?

"Coulomb counter" and "coulometer" are interchangeable terms, so don't let those confuse you.

As to identifying by functionality, if I understand your question properly look for an amp-hour or watthour display, or perhaps "remaining capacity" or SOC (state of charge).

You don't need anything too esoteric for a battery in the back of a ute, IMO, but of course, it's up to you.

I installed one of these from eBay.

In operation it looks like this:



100% = SOC.
102Ah = capacity remaining in the battery. (You enter battery capacity during setup)
The battery symbol is a graphich display of remaining capacity.
00:00:00 = time to full charge (if charging)
12.36 = battery volts
0.058A = current (charging or being drawn) If the battery is charging the display flashes. If it is discharging the display remains steady. It is the overall result of charging and load. eg 10 amps charging and an 8 amp load would display as a 2 amp discharge (steady display).
0w = Product of current and voltage.

.
Yes Briste, the Simarine is a bit of overkill for your needs but I had tanks and stuff and did not want multiple monitor displays.
What would serve you well would be the Enerdrive ePRO-Plus which provides battery state of charge, voltages and alarms in a compact form. Much the same as the Victron monitor.
Now I have a proposition that you may find attractive. I have a surplus ePRO-Plus with 300A shunt that has never been installed and is all yours for free. Click below on 'My Profile" and you will see my email address to respond with the address to post it to.

Briste,

Take Allan's offer! :-)

Cheers

Never look the offer of a battery monitor in the mouth / display / whatever, I'm sure my father once told me. That's incredibly generous Allan - I have just emailed you.

Thank you everyone for your perseverance through this accidentally hijacked thread. Time to wrap it up.

@Frank - I hope that the Mao's last dancing coulometer and the PRF speak the same dialect.