DEEP CYCLE BATTERIES and BUSH POWER

[condor22]

What's the ambient temp of where the batteries are?

Also, When charging a battery there is a "surface charge" present which takes several hours to dissipate to then give a "At rest" voltage. As this is temperature affected, I prefer to leave a battery 12 hours or overnight. i.e if I charge my van AGM from my 240 VAC charger to float (it's set to 13.2 Float and for a reason) then turn the charger off, the battery voltage will still read 13.2 and gradually reduce to it's at rest V. As I said, overnight is best, if it reads 12.8 to 12.9 then it's in good condition.

A similar situation occurs with a reasonably full battery under load i.e. I know that if I turn my Engel on initially pulling 3.2 A the voltage drops from 12.8 to around 12.5/12.6. However if I add another 6 A from my 12 V oven, it drops to 12.3/12.4 under a total load of close to 10 A.

The bigger the load, the lower the voltage drops. Then you have the situation of what I term "surface load" as apposed to the surface charge. When a load switches off, it takes time for the battery to recover back to it's State of Charge Voltage, which again is temperature affected. However, the time taken to recover is generally a lot less than when charging. RR I'm probably "preaching to the converted" as far as you are concerned, but most of the above is for others less experienced.

My point is that, given the variables of temp, condition, size of load etc etc the only true way of knowing a batteries state of charge is battery/load monitor (BMS) than measures Amphours in and out and calculated the difference against the size of the battery. Even here over time, the error can compound without a reset.

More....... re float voltage and BMS reset

 

[condor22]

Float V - When an AGM floats at 13.8 as many chargers, solar controllers and DC-DC do it is still gassing off to a small extent. This can reduce life expectancy. The Threshold at 25 degrees C is around 13.2 V, which is why I set my 240 VAC charger to this V. I also had my Victron solar controller re-programmed to that float voltage.

BMS reset - As with most, my BMS measures AH in and AH out then calculates the net + or - affect on the battery. They have a tolerance on their measurement capability which compounds over time. So, the longer it is in use, the further away from actual in can get, especially with all the variables associated as I mentioned in my last post.

My answer - My BMS has a 100 A shunt for the main battery charge/discharge on the negative lead. It then has 4 small wires, 2 go to the digital display, one goes to the battery positive to power the display/electronics, the 4th to BAT -.

The BAT + has an inline 1 A fuse (display etc), I open it and disconnect the fuse for at least 10 seconds, then reconnect. This resets the display and computing side of the BMS. My main use is 2 trips of 8 or so weeks prospecting when I'm off grid. The van is in my driveway on solar to keep the battery in constant 100% SOC (State of Charge), so a day or two before departing, I reset the BMS. As far as time goes, once or twice a year is what I would do if used constantly.

Disconnecting does not affect the BMS's ability to gauge the health of the battery as this is measured reasonably quickly i.e not total time dependent.

RR it looks like your little fridge is very efficient, but again ambient? Pomland aint gonna give 60 C in the back of a 4by. but then you lot drink warm beer layful: :beer: :beer: :beer:

 

[Ridge Runner]

The Ambient temp of the batteries is just over 20*c,

I left the batteries to sit for 36 hours before hooking up the fridge so the surface charge had a chance to drop allowing the batteries to settle, At that point the voltage was over 13.36 Volts

I also ran the same test in 38 and 39*c,

The reason my batteries seem to hold that much Voltage is because of how I Charge them using a Normal Charger and then Using my smart charger and after that I run the repair mode which cleans up the Plates, This Mode is mainly meant for Lead Acid Batteries But I also managed to recover My AGM Battery using both Chargers as they reset the BMS in the AGM.

If a Lead Acid Battery still plays up after that I will run the repair mode again and in extreme cases 3x in total, This Repair mode can Pulse 16.5v for a fraction of a Second and it is programed to work it's way up to around that high over a period of exactly 4 hours,

The Noco Chargers are really good for conditioning batteries, I use a Normal Charger for Bulk charging Lead Acid Batteries and when finished I then let the Noco do it's Pulse equalization mode and then run the Repair Mode, I do this every 4 to 6 weeks as well as use a Fridge to draw out between 20 to 50% from the Batteries once every 4 to 6 months, Doing this has also raised the CCA level by 11 to 14% on average,

It is a lot of messing around but doing this twice a year or so makes sense because No charger or solar setup delivers a true 100% full charge where On a good day the best they can do is between 90 and 96% on average which means the battery will loose that extra 4 to 10% of Storage ability so a 100Ah becomes a 90Ah and in some cases worse and that becomes more critical on smaller batteries,

For normal Lead Acid Batteries the Noco will put out 14.5v and if it is a Cold battery then the Cold setting is 14.8v, It does this in pulses and it removes sulphide build up on the plates which is the main cause of batteries loosing their storage ability and it can also be done with a Normal Charger but only for and hour or two, Once this is done I hook up the Noco and run the Normal charge mode and when it has finished clicking "Long After" the green light has stopped flashing then I run the Repair mode and if a battery is really bad then after doing all that I re run the repair mode,

I took delivery of these batteries on the 19/07/17 and they measured at 12.6v yet they were meant to be fully charged according to their website, Needless to say they are in better condition than they were when I got them,

The Info about taking the Voltage up to 14,8v came from Battery University, Also Noco make their chargers put out the same voltage.

All these Voltages Go against what we are all taught but B/U and Noco seem to be on the right track, because it takes about 65 hours before the voltage gets to 12.700v running the fridge at 1-2*c, and the fridge has been running for 107 hours 27 minutes before it got to 12.502v.

Due to the Sun Hours I get, my small Lithium packs are best for winter because they are easy and fast to charge and Lead Acid are better for the Summer months. which means staying in one spot for a day or two even if I run 2x 150w panels in series just so I can get the higher Voltage for the MPPT.

 

[condor22]

My van battery is now 5 years old, still holds 12.8/12.9 at rest, 4x4 Aux is now 2 years and the same voltage. Happy with that. Both BMS's show both batteries in as new/very good condition. They both hold voltage well.

When in use, I regularly pull between 35-40 AH from the van 135 AH. Even in mid winter, regularly see the 200 W solar fill it by mid afternoon. Plenty of Sun hours down here, lol.

Can't say re the 100 AH car aux, this next trip will be my first full trip (Covid apart) where I will see how the 110 W goes with the new controller, thru end April to mid June.
Plus will be taking the Brass Monkey 15 lt for occasional freezer use.

My concern at the present is one of my 150 W inverters, I can't find the bloody thing. Went to the car drawer this arvo, not there, and due to my "tender years" can't remember if I took it out and/or where I put it if I did. Guess what tomorrow's job is.

 

[Ridge Runner]

I thought about going to 135's as they seem to have the biggest plates which means they can take a beating and hold a heap of power,

I have 6x 150w matching panels I would have to link them 3+3 giving over 24v @ about 15A+/- but it is pointless unless they are in a fixed location because of the lack of Sun, It's crazy because I can charge my 40Ah Lithium pack with a 120w panel in just a couple of hours but it does not pay to draw too much from my AGM's and my Lead Acid batteries,

I nearly bought one of the Brass Monkey fridges the other day, but until I deliver a couple of fridges I got for people I thought I better wait, They seem to be the one to beat.

Would a 300w have a low enough draw just to give you a bit of headroom ? Trouble with inverters is every time you buy one they seem to get bigger and bigger, I started off with a 300 and then an 800/2000 which I gave to my brother and he gave me a 600/1500 and then I bought a 1500w/3000w True sign wave and now I have gone back to my 300 and the 600 due to the "No Load" draw the bigger ones have.

 

[condor22]

I mentioned this previously... but.

My electrical requirements in the van; The 12 VDC system in the van, the only things that are 240 VAC are the Aircon which I don't use in winter when detecting. The rest I can run from the Honda 2kVA, small poly collapsible kettle @ 1600W), microwave @ about 1140W, small hairdryer for the wife @ 1400W, 240 VAC charger if needed.

They are all way to much for an inverter from 130 AH. I have an ultrasonic cleaner for the gold I find which is 240 VAC only and runs from the 150 W inverter when needed.
The rest are all battery chargers i.e. phone, detector batteries etc and are either all chargeable or used on either 12 V or 5 V USB including my laptop. Oops forgot my electric shaver, it's battery but also only 240 VAC charging and again the 150 W will do it.

So, I take the attitude, if it can be powered or charged from 12 or 5 volts, do so, the couple of items that can't will work from 150 W inverter. Anything else, I crank up the genny.

I rarely use the kettle as I also have a stove top on LPG. My wife has only been out with me once in 6 years and my hair is shortish and I don't use the dryer.

An example, I don't see the point in inverting 12 VDC to 240 VAC, plugging in the GPX5000 battery on charge which steps it down to 12 VDC (or 8 V, not sure) to charge it. Too much efficiency loss, lol.

In other words, there's nothing, I have that a 300 W can do that my 150 W isn't already doing. My 1st van had 200 AH (2 x 100 AH) of battery, 64 W of solar, 300 W inverter and a 12 volt 90 lt fridge. It was in the days of 240 VAC TVs. No battery monitor, it pulled 27 Amps at 300 W. So when I also ran the 240 VAC satellite the first time, I wondered why after 4 hours of TV my lights started to dim. So not a big fan of inverters for heavy duty use.

As an example, if I used my microwave from an inverter 1140 W divided by 10 (not 12 due to efficiency as a rule of thumb it would pull 114 amps. If I used it for 6 minutes that's only 11.4 amps. But I would need at least 200 AH to take the 114 amp load if not more and some serious copper. Pull a cord and an egg cup of unleaded is a lot easier. Let's face it, the 32 kg of genny = or < the extra battery weight.

 

[condor22]

Found my inverter, remembered I took it into the shed to remove the cig plug and replace it with a fused Anderson.

I also checked my 18 V Ryobi chain saw, it has a 5 AH battery, which I can also use with my angle grinder, jigsaw and a small vac cleaner. It has a 240 VAC charger that according to the plug top of the rapid charger draws only 60 W so it should also work from my 150 W inverter.

BTW I do have 2 identical inverters, 1 in the van, 1 in the 4by.

I think I once checked a couple of years ago, with the use of a power board running from the inverter, I could charge my 18650 batteries, the GPX, battery and my wireless Tx/Rx all at the same time. But as I said, I can do all of them from 12 or 5 VDC anyway.

I have a Bosch 2 battery drill I keep in the shed, but am looking to get a Ryobi Drill, skin only to take away, using the same battery.

 

[Ridge Runner]

Found my inverter, remembered I took it into the shed to remove the cig plug and replace it with a fused Anderson.

I also checked my 18 V Ryobi chain saw, it has a 5 AH battery, which I can also use with my angle grinder, jigsaw and a small vac cleaner. It has a 240 VAC charger that according to the plug top of the rapid charger draws only 60 W so it should also work from my 150 W inverter.

BTW I do have 2 identical inverters, 1 in the van, 1 in the 4by.

I think I once checked a couple of years ago, with the use of a power board running from the inverter, I could charge my 18650 batteries, the GPX, battery and my wireless Tx/Rx all at the same time. But as I said, I can do all of them from 12 or 5 VDC anyway.

I have a Bosch 2 battery drill I keep in the shed, but am looking to get a Ryobi Drill, skin only to take away, using the same battery.

Good, well done, I have days like that too, layful: layful: layful:

Ya know None of the Ah Vs Run Times never ever match the maths, Hence why I have kept testing fridges Vs Batteries over the years and I can't think for the life of me why ??

As I said I have very high Voltage at the Start of 13.36v +/- and it takes about 64 to 67/68 hours to get down to 12.7. And at each cycle the fridge eats about 0.022v dropping down to 0.015v and as the Voltage drops the amount of cycle voltage also drops, Like now after 137 hours it is chewing 0.003v from the remaining Voltage every time it cycles which is a good thing because the Battery lasts longer,

But It does not matter if I use AGM's or Deep Cycle Batteries the Maths never Match,

IE, 2x 115Ah DC batteries gives me 230Ah to play with and @ 50% = 115Ah of useable power. My fridge has run for 137 hours and chewed 44.909Ah and my Battery Voltage is reading 12.412,

None of the above makes sense So I hooked my Fluke DMM in Line with the kickass Type Meter and found it was reading 0.05Ah LOW So I corrected the Ah figure and that made a slight increase in the power used But when the Fridge shut off then I notice at a glance that the FLUKE was reading 0.0761Ah which happened to be the Power Draw the Kickass Meter was Drawing ??

So I did the Maths, :/ :argh: :argh:

0.0761 X 137.35 Hours = 10.452335Ah / 137.35 hours is 5.7 Days and with the offset this meter will loose over 2.2Ah per Day.

Add it's offset reading and the 10.452*** etc has Chewed a grand total of 12.697+Ah So Far

This Kickass Meter In total is Chewing Up 23.2744% + of the Total power that has been used over the 137.35 hours and by time I hit the 200 hour make it will of eaten over 15.22Ah, Plus what ever the Offset is missing which means I have Lost/Used 28.27% more power than has been recorded.

So Bottom line is If you are using one of those Kickass Meters It costing over 20% of the total power used and when you are reading the Ah used Vs the Voltage you can easily put your Batteries in to the Danger Zone.

And Using the Fluke to measure the Voltage It says I still have over 12.407v and after working out the meter loss and the Offset compared to the Voltage I have left which is around 75% I have used 57.606783Ah which is awful close to 25% of 230Ah.

Problem Solved :inlove: :inlove: :inlove:

 

[condor22]

Not sure what DC battery means in your text. But It does not matter if I use AGM's or Deep Cycle Batteries the Maths never Match, Quote

FYI An AGM battery is a deep cycle battery, so is a GEL Flooded Lead Acid etc. So by Deep Cycle, do you mean a Wet Cell Deep Cycle?

 

[Ridge Runner]

Not sure what DC battery means in your text. But It does not matter if I use AGM's or Deep Cycle Batteries the Maths never Match, Quote

FYI An AGM battery is a deep cycle battery, so is a GEL Flooded Lead Acid etc. So by Deep Cycle, do you mean a Wet Cell Deep Cycle?

By DC I meant Deep Cycle For Short, Which I should of written because it was only 9 letters and this has taken me 89.

I know AGM and Gel are Deep Cycle Batteries, That's not the issue I was having a problem with.

 

[condor22]

How old are your 2 x 115 AH AGMs, if you don't mind me asking?

I ask as, 44 AH of fridge use from a 230 AH bank is only about 20% of capacity. I use around 37 AH from my 130 AH a day on average and that's around 28% of capacity.

When I get up in the morning, I usually have the panels working a little and also turn the diesel heater off, so battery state voltage is not at rest. But a couple of times I've turned the panels off the night before, to check the morning voltage. As I make brekky using LPG, I actually have no load on the battery at all and it hovers at 12.5 V until I turn the panels on.

I do know that my BMS has a parasitic load, so if I turn all loads and charging off, but leave it on, it slowly drains the battery. It's LCD display has a timeout function, I've set to 10 minutes. After this it has a current drain of 1.5 mAh = 36 mAh over a day, not worth considering as I leave the panels on all the time anyway.

 

[Ridge Runner]

I took Delivery of the 2 115Ah Batteries on the 19/7/17, So they are 3 years 7 months and 9 days old,

My AGM's are 2 X 80Ah and I only use one to power the Fridge,

The Amps used Vs the Reading Vs the Draw of the Meter, Using 2 X 115Ah Lead Acid Deep Cycle Batteries,

Meter Reading = 44,909Ah @ 137.35 Hours. ( 137h 21m )
Meter reading Low by 0.05Ah When Running.
True Ah Used = 47.15445Ah,
Meter Draw = 0.0761 Ah X 137.35 Hours = 10.452335 Ah.

True Ah Used, = 47.15445Ah.
Meter Draw, = 10.452335Ah,
Total Used, = 57.606785Ah.

Battery Voltage @ 137.35 Hours = 12.407v.
Battery Voltage @ 75% as Per Chart = 12.40,

2 X 115Ah = 230Ah,
100% / 230 = 0.43478260869.

0.4347826869 X 57.606785Ah = 25.0464282605% power Used.

Useable Power @ 50% = 115Ah,
2 X 57.606785Ah power used = 50% +/- = 115.21357Ah.

If The Meter is reading 0.05 Low Then take the figure of 44.909Ah,
44.909 X by 1.05 = 47.15445Ah which is the correct amount of power used.

Also Note those kickass type meters use almost 2Ah per Day from your Solar/Battery on top of your Power Needs..

0.0761 X 24 = 1.8264Ah Per Day/24hrs.

I hope that explains It Better.

 

[oldtimerROB]

I'm going to buy a deep cycle battery from Aussie Batteries online. A 120 Ah costs about $350 with a plastic box supplied and has some connections for 12 V appliances like a fan heater to heat my van in winter. I read in your first post that AGM batteries are the safest but I am always fearful it might explode.. My question is can I install it near my bed and will it be advisable to do so. I have no other options other to place it on the floor of the passenger seat which would be inconvenient if I want to carry a passenger. The charging will be via a 200 watt solar panel during daylight when I am detecting. A second battery would also be very handy if the car battery goes flat and I am in a remote location.

 

[Ridge Runner]

I'm going to buy a deep cycle battery from Aussie Batteries online. A 120 Ah costs about $350 with a plastic box supplied and has some connections for 12 V appliances like a fan heater to heat my van in winter. I read in your first post that AGM batteries are the safest but I am always fearful it might explode.. My question is can I install it near my bed and will it be advisable to do so. I have no other options other to place it on the floor of the passenger seat which would be inconvenient if I want to carry a passenger. The charging will be via a 200 watt solar panel during daylight when I am detecting. A second battery would also be very handy if the car battery goes flat and I am in a remote location.

Rob I like the extra Voltage that Deep Cycle batteries which adds to the Run Time and I have 3 of them But AGM are designed to take a physical beating and can take the rigors of off road travel and they can be mounted at any Angle, Originally they were inverted for the Military and Aviation so it would take a lot for one to explode unless it was exposed to excessive heat or abuse,

You have a good panel to charge one so it might be worth going with AGM because you get a lot of sunlight and the AGM's charge faster than normal deep cycle batteries, I would go with what Condor says, erfect: :Y:

 

[condor22]

Rob - AGMs are designed for confined space use. In a battery box, by your bed is as safe a place to install it as any.

I'm assuming you have a motor home and what kind of "fan heater" are you talking about?

Is your charging limited to solar only?

 

[bicter]

Rob - AGMs are designed for confined space use. In a battery box, by your bed is as safe a place to install it as any.

There is a difference between being "safe" and "safer"
Any Lead acid battery, including AGMs, should be vented to atmosphere and not installed in conjunction with spark-producing equipment.
This is due to the fact that any lead acid battery will vent hydrogen in an overcharge situation.
Overcharge situations can occur when chargers or solar regulators fail.

 

[condor22]

Rob - AGMs are designed for confined space use. In a battery box, by your bed is as safe a place to install it as any.

There is a difference between being "safe" and "safer"
Any Lead acid battery, including AGMs, should be vented to atmosphere and not installed in conjunction with spark-producing equipment.
This is due to the fact that any lead acid battery will vent hydrogen in an overcharge situation.
Overcharge situations can occur when chargers or solar regulators fail.

Agreed, but I did say "as safe a place to install it as any." My van AGM is in a battery box under the dinette seat and in the same area as a 240 VAC charger, solar controller, DC-DC charger, terminal blocks, shunt and fuses. My 4x4 AGM is in a battery box in the rear of the wagon with a DC-DC, solar controller and fridge.

But as I have said in other posts - correct wiring, fusing, charging etc etc helps to mitigate risk.

For the purposes of Rob's question, I believe my answer is, that it should be ok if done properly.

I had a mantra I used in my working life as a designer - No matter how foolproof you make something, some "idiot" will come along and screw it up. In other words "Foolproof aint Idiot proof." lol.

 

[Solid Luck]

I'm going to buy a deep cycle battery from Aussie Batteries online. A 120 Ah costs about $350 with a plastic box supplied and has some connections for 12 V appliances like a fan heater to heat my van in winter. I read in your first post that AGM batteries are the safest but I am always fearful it might explode.. My question is can I install it near my bed and will it be advisable to do so. I have no other options other to place it on the floor of the passenger seat which would be inconvenient if I want to carry a passenger. The charging will be via a 200 watt solar panel during daylight when I am detecting. A second battery would also be very handy if the car battery goes flat and I am in a remote location.

Don't know where you are located but if you have an Aldi close by they have some gear going next Saturday.
I was going to go for this setup but it is way too heavy for me. 30 Kg for a battery is not something I can just lug around.

 

[Ridge Runner]

I'm going to buy a deep cycle battery from Aussie Batteries online. A 120 Ah costs about $350 with a plastic box supplied and has some connections for 12 V appliances like a fan heater to heat my van in winter. I read in your first post that AGM batteries are the safest but I am always fearful it might explode.. My question is can I install it near my bed and will it be advisable to do so. I have no other options other to place it on the floor of the passenger seat which would be inconvenient if I want to carry a passenger. The charging will be via a 200 watt solar panel during daylight when I am detecting. A second battery would also be very handy if the car battery goes flat and I am in a remote location.

Don't know where you are located but if you have an Aldi close by they have some gear going next Saturday.
I was going to go for this setup but it is way too heavy for me. 30 Kg for a battery is not something I can just lug around.

https://www.prospectingaustralia.com/forum/img/member-images/4748/1615788754_20210315_170745_1.jpg

You've changed your user Name ??

 

[Solid Luck]

I'm going to buy a deep cycle battery from Aussie Batteries online. A 120 Ah costs about $350 with a plastic box supplied and has some connections for 12 V appliances like a fan heater to heat my van in winter. I read in your first post that AGM batteries are the safest but I am always fearful it might explode.. My question is can I install it near my bed and will it be advisable to do so. I have no other options other to place it on the floor of the passenger seat which would be inconvenient if I want to carry a passenger. The charging will be via a 200 watt solar panel during daylight when I am detecting. A second battery would also be very handy if the car battery goes flat and I am in a remote location.

Don't know where you are located but if you have an Aldi close by they have some gear going next Saturday.
I was going to go for this setup but it is way too heavy for me. 30 Kg for a battery is not something I can just lug around.

https://www.prospectingaustralia.com/forum/img/member-images/4748/1615788754_20210315_170745_1.jpg

You've changed your user Name ??

Yes. Hard Luck got buried at the last meetup.