DEEP CYCLE BATTERIES and BUSH POWER

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How far a battery voltage drops under load is variable as it depends on the load, state of charge, ambient temp, age and condition of battery. I'll go out and check shortly. :)
 
Did a check and keeping it simple, lol.

Still have not used the 4by since Saturday, now 3 days, ambient temp 20 C.

Aux Bat voltage is 12.8 V at rest. Turned the Engel on for 5 minutes (drawas 3.2 amps, but once running drops to 3.0) the voltage dropped fairly quickly to 12.6 V. To show the point that it depends on load, I then turned the Travel Buddy oven on with the Engel still running. Total load approx 9.2 amps, the voltage dropped to 12.4.

This shows that the voltage drops more, the higher the load. I ran the oven for 2 minutes and the turned everything off. After less than a minute the voltage recovered to 12.7 V, which I would expect to be the case, from a battery that has had no charge for 3 days. :)
 
condor22 said:
Did a check and keeping it simple, lol.

Still have not used the 4by since Saturday, now 3 days, ambient temp 20 C.

Aux Bat voltage is 12.8 V at rest. Turned the Engel on for 5 minutes (drawas 3.2 amps, but once running drops to 3.0) the voltage dropped fairly quickly to 12.6 V. To show the point that it depends on load, I then turned the Travel Buddy oven on with the Engel still running. Total load approx 9.2 amps, the voltage dropped to 12.4.

This shows that the voltage drops more, the higher the load. I ran the oven for 2 minutes and the turned everything off. After less than a minute the voltage recovered to about 12.7 V, which I would expect to be the case, from a battery that has had no charge for 3 days. :)

Cool thanks for that,

Mine sort of did the same dropping to 12.6+ and after about 10 minutes it was reading about 12.46 and as soon at it shut off it started to read 12.6+ and then slowly climbed back up to 12.75v add to the fact that the Peak Ah used upon start up was 4.66 and then within a split second it dropped to 3.5Ah /3.6Ah whilst running, That might appear to be high but it will run for 12 to 16 minutes and then shut off for 2 hours, The end results were it used 5.292Ah in 9.533 hours or 9 hours 32 minutes which means it is using 0.555Ah per hour X that by 24 hours = 13.322Ah per 24 hours Set At 0*c.

At the moment I have the AGM hooked up to the Noco with the Fluke Multi meter hooked up to the Clamps recording the minimum voltage so I can record at which point the Noco will fire up and start it's top up Charge and what it's shut off Voltage is,

The Noco Chargers are brilliant chargers but the Manual is little more than a Mud Map, As are the Noco Booster Packs Manual there is so much info missing,
 
Just went out to the car to check the Aux Bat volts = 12.8 V. So back to where it was and I still haven't started the engine.

After yesterdays small load v voltage test the battery is holding voltage.
 
Last point on the above posts - I finally got into the 4by to go out today, 6 days without starting the engine.

As noted I did briefly fire up the Engel and the Oven and the at rest voltage 2 days ago was back at the 12.8 volts, but was at 12.7 volts before I started today.

I should note there are 2 parasitic loads on the battery;

1. The BMPRO battery monitor that runs at a max of 10 mA, which would account for a max of 1.4 AH during my not driving.
2. I also have a digital voltmeter I can see anytime. It is described as self powered with no spec on its power use. My guess is no more than the BMPRO.

Conclusion - After very little load (2-3 AH max) the battery is still holding a good voltage. But it also shows that if left without charging for longer periods a battery will lose capacity.
 
Ridge Runner said:
...

Lithium is nice but the cheapest 100Ah Li I have found over here is 699.00 which is about $1260.00 the average price of them here is around $1800.00 and there is no way I am going to fork out that amount, I got the 2 Dometic PLB's and they will run my fridge for days and Once this AGM has been tested running the fridge I might fit it back in the Van as a house battery, The way it is holding power it is almost as high as the new AGM I just bought so I am expecting good things to come from it,

I was toying with the Idea of getting a 230Ah AGM but weighing around 57kgs might be too much to haul around all the time,

Where do you live, UK? Thats so expensive for a lithium... Renogy has a 100AH for $799 AUD that looks really nice. Best value I have seen. Check will prouses review on YouTube: https://m.youtube.com/watch?v=aahHWaV6Zdk

Hes pretty brutal typically and this gets a great review from him.

Their monitoring panel thingy is pretty cheap as well. If I upgrade from lead agm with Projecta IDC25, it will be to this renogy battery and probably their DCDC charger.
 
I charged up my AGM and after 24 hrs with nothing connected it was reading 12.915v and at 48hrs = 12.885v and at 72hrs = 12.867,

So I guess it is close to near perfect again, which is not bad considering when I took it out of the Van it was reading 11.70v and would never hold above 12.39v or less. :Y:
 
Got the solar panel remounted on the 4x4
As was - The basket and roof rails were already up there, but by the time the basket was covered by the panel and the Maxtrax, there was next to no room to tie anthting else to.
1608191524_rear.jpg


Removed the basket and the roof rails, they are curved and difficult to mount anything to (Holden OEM)
1608191537_rear_ver_2.jpg


Had the alum angle bent by a workshop, profiled the edge to the curve of the roof and used the roof rail mounting holes on the car. Saves about 15 kg of weight and about 6" in height. (That's 150mm for the younger gen, lol)

Next job is to mount the Maxtrax :)
 
Had a look at their web site. $995 for the Lithium NMC chemistry. As they provide the 8 amp charger, it sounds like a low charge rate i.e if you use 80% or 80 AH then my math says a 10 hour charge time.

Perhaps you can clarify. :)

Other than that looks good.

Some Qs

As I don't have the manual, is the charger 240 VAC or 12 VDC? In other words from the car
Does it have a solar charging option?
Can it be charged whilst being used?
 
Hey Condor22,
I'm just of to work so happy to discuss further tonight.
As stated in a previous thread I'm a total simpleton when it comes to this stuff.

I do know it was half full when I got it and took about 12 hours to get to full plugged into the mains at home. I believe the ciggie charger is DCDC? 5 amp so it does not cook the cars wiring.

At about the halfway mark now since tuesday morning running a 22 litre BM fridge sitting in the back seat non stop.
 
I'm loath to discuss Lithium, as I'm still learning, lol. However, if anyone is interested, I'll note some of what I've found out. As I may have mentioned, there is a friend of mine that runs a business called Nimbus Engineering, which specialises in motorhome and caravan off grid power. He supplied my caravan panels and Victron controller. As an aside, he reprograms the float voltage of the Victron in float mode form 13.8 V down to 13.1. The reason, an AGM continues to "gas" off at anything over 13.2 V so why stress it. :)

On to Lithium, as an electronics engineer/designer, he receives a lot of technical data from all over the world. The one he mentioned in particular was that an Australian company received funding (over $9 mil) to test dozens of Lithium deep cycle batteries from all over the world. The tests were broken into 8 phases and conducted over 18 months and resulted in a 300+ page report, he has a copy of. I've only briefly discussed this with him and comments made (by him) include; "At the end of phase one, 15 batteries failed" (tests got progressively heavier duty, including loads, charging and environmental). "At the end of each test phase, more and more batteries failed".

The final comment; "At the end of phase 8, only 2 batteries had survived and passed all phases, a Tesla and a Pulmantech."

Which leads me to mention the latter. He's not a huge fan of Lithium, but is now a supplier of the Pullmantech. I've seen one and although he's sold a few, still to do some testing of his own. It has an all metal case, roughly 11kg, has an internal BMS, an on/off switch on top of the battery (push button), a gauge showing battery capacity and is a 100 AH. I believe it is a bit under $1,000.

More.....
 
On the testing he has done, he found that when connected to solar through a Victron controller, it doesn't charge. He believes this due to;

When a Victron controller is connected to an AGM, it looks at the batteries condition and state of charge (SOC) when deciding what stage and charge rate to use.
Unfortunately, as a Lithium is fitted with a BMS between the battery cells and the terminals, the Victron doesn't see the battery, it sees the BMS. This may be the case with a lot of Lithium batteries and other good brands of solar controller, so be aware of this possibility.

Next, 240 VAC charging. A 12 V lithium does not need stage charging, its best charging voltage is 13.8 volts up until it's 98% full. The last 1-2% of charge is forced in at around 14.5 V, which briefly puts the battery under stress. His recommendation, use the power supply mode of a good quality charger, which in most cases is 13.8 V and forget about the last 1-2%.

If you have a 100 AH and run it down to 20% SOC, you used 80 AH from a full battery v 78 AH if at 98% SOC. His comment, "Why put a battery under stress for 1 AH?"

Where this becomes an issue. - I've done a lot of Googling and to date have not found a DC-DC charger or solar controller with a 13.8 V power supply mode. Which means, those that are available will output up to 14.5 V at some point.

That's not to say a Redarc, C Tek, Projecta etc won't charge a lithium, they will. The question it at what cost?.

More.....
 
Cycle life -

With my AGM, I regularly use around 35 AH per day, so I charge that every day. Mainly solar with genny 240 VAC top up if needed. So that is 1 cycle from my AGM per day for 25% of capacity. My AGM cycled at this rate and charged properly, will give me about 10 years service as I only use it for about 4-5 months of a year and keep it at float when not used.

With a lithium, I can draw 35 AH on day one, then another 35 AH on day 2, for a SOC of 30% (70 AH used). Then charge it, which is one cycle every 2 days. On that basis and with the same usage as my AGM, the lithium should last closer to 30 years.

So here's the comparison -

Price
AGM - My last 100 AH cost me $309 (Home of 12 Volt, I asked for best price and got a discount) So 3 of them should last me 30 years at a total cost of $927 or so.
Lithium - For the same time $995.

Weight
AGM - 31 kg
Lithium - 11 kg

Charging
AGM - I like many others already have AGM charging from 240 VAC, DC-DC and/or Solar. So whatever you have already spent.
Lithium - Although I've seen quite a few going to lithium and those I know have been told, your AGM setup will charge the Lithium no worries. Yes it will charge it, the question is, what will that do to the longevity of the battery.

I don't think there are too many lithium users that have been around for 10 years, yet. :)

So my thoughts are; If you are setting up a new system and choose lithium, great, but do your homework, there are some real cheap and nasty Li batteries out there.
If you already have AGM setup with all the necessaries, the only gain is 20 kg and more leeway in how often you charge. For me, not worth the expense.
 
My Dometic PLB40's take the power straight off the solar panel because it already has a built in charge controller / DC to DC Charger, It come with a Cigar lead with an Anderson that plugs direct in to the PLB and it has a round 8mm round socket to charge it via the AC pack, And you also plug the Solar Panel direct in to the Anderson Socket,

That said there is no way of knowing what is going in to the Pack so I have made up a lead so I can use one of those kickass type meters so I can see what is coming from the panel and see what the PLB is taking. :Y:
 
condor22 said:
Had a look at their web site. $995 for the Lithium NMC chemistry. As they provide the 8 amp charger, it sounds like a low charge rate i.e if you use 80% or 80 AH then my math says a 10 hour charge time.

Perhaps you can clarify. :)

Other than that looks good.

Some Qs

As I don't have the manual, is the charger 240 VAC or 12 VDC? In other words from the car
Does it have a solar charging option?
Can it be charged whilst being used?

Hey condor22. I wont be much help but I'll try.
Need the portable battery specialists to help out here.
Ciggie charger I have posted a pic above. Confirmed with the manufacturer that it will run fine and not cook the cars wiring. They also have a more powerful car charger that is 10 amp but that needs to be put together by a auto electrician.
Charge time was posted above as well. The pic is now charging from the socket at home.
It does have solar charging option.. Either unregulated via the 2 knobs on the left or regulated via an Anderson plug. The retailer I purchased from had a look at my old solar panels and said they should be fine as they have a regulator on them. He cut of the clamps and installed an Anderson plug for me. Just emailed the manufacturer, he gets back pretty quick with an answer but I'm still not sure what he means. Maybe I'll ask him to join the forum and clarify a few things :( .

And yes, it can be used whilst charging.

Is it a good unit? Who knows? Time will tell. It will get a right royal thrashing over the next few months. Not to the point of running it down to 0%. I'll fully charge at about 50% and use the ciggie charger whilst driving around. Plus I'm always near my car so the windows will be down in the heat.
For me, the appeal is the portability. Cost to install a dual battery agm in my ute would have been about twice the price. I was looking at getting an AGM battery in a battery box but at over 30kg that is way to heavy for me.
1608276407_20201218_174653.jpg
 
I've had quite a few chats with my mate and he knows I'm interested in the Life Po4 100 AH. But my issues are; (relevant to when I go prospecting)

My 4x4 and caravan have differing needs - 4x4 is primarily charged from the DC-DC charger when driving and the solar panel when not. The Engel is on 24/7, the Travel Buddy oven gets used 1 hour most days for lunch and if I carry it in the 4by the Brass Monkey. My caravan is primarily charged from solar and as I run the genny most days for microwave or hot water heating (every 2nd day for a shower), I top up the battery using the Electro 240 VAC 30 A charger. Also, when out prospecting, as the fridge is on LPG, there is absolutely no load from the battery when I'm not at the van.

I would only ever use 240 VAC on the 4x4 if both other options failed and have only used DC-DC on the van when I'm in an area I can't use the genset and the weather is bad enough to affect solar.

That being said, I can not see me using lithium in the 4x4, as when home I rarely use the Engel and almost never the oven. So for 4 months a year not worth it. I could take the same tack with the van re use, but the usage demand is higher in it and might justify lithium, probably not, lol.

My research points to power supply mode being the best voltage to charge a lithium, the Pulmantech's BMS will actually regulate what current the cells receive in charge of the 30 A I have. But this means running the genny to charge it.

As I mentioned, I have not found a solar controller or DC-DC so far that has a "power supply" mode of a constant 13.8 V. I did look at a 25 amp DC-DC voltage regulator, also Electro. It has a variable input of between 8 & 40 volts, so will handle a solar panel voltage or indeed a 24 V system. It has a regulated 13.8 V output at 25 amps, but it states in its specs that it is not to be used as a battery charger. My mate stated that is because, although the voltage is regulated, it has no current limiting ability. If the battery it might charge wants more, it could burn out. Whereas my 240 VAC charger is both V & A regulated even in power supply mode.

Where to from here, well keep looking, but for now, everything I've set up is working great, so "if it aint broke don't fix it", lol. :) My main reason for posting this is, to warn others to be cautious, many sellers are not technical, don't know their product and only want to part you from your hard earned. I say many, but not all. :)
 

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