GEL or AGM (2 Viewers)

[canopus]

My missus will have a dickie fit if I mention more expense.

 

[canopus]

Just in case I can do some man maths, which model Votronic would I require to replace at the Stecca @Lenny HB ?

 

[two]

Stick with Gels. I've had much better life from Gel than AGM. There seems to be conflicting information about the required regime for managing AGM, so I'm doubtful that some of the kit available for AGM will do the job required.

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[funflair]

Votronic 350 mppt duo will handle 21amps Ken.

Martin

 

[manda3000gt]

MorningStar MPPT solar controller the best available although not cheap, superior charging programs with temperature compensation
30amp model should be good for your needs

https://www.morningstarcorp.com/products/tristar-mppt/

plus your going to need the display meter

https://www.morningstarcorp.com/products/tristar-digital-meter-2/

 

[Lenny HB]

You don't say how much solar you have but models are obvious, 100 MPP is up to 100 watt, 250 MPP - 250watt, 350 MPP - 350 watt, 430 MPP - 430 Watt.
I just fitted a 350 MPP, 250 and up have a AES output for the fridge, if you have an AES fridge with a S+terminal it tells the fridge to switch to 12v when batteries are charged and you have excess solar.

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[canopus]

Have the original 165w Kyocera which was on when we bought the van plus a 200w we had fitted in Morocco a few years back. The original Stecca 10A controller was swopped out for the Stecca 20A as previously mentioned.

 

[canopus]

MorningStar MPPT solar controller the best available although not cheap, superior charging programs with temperature compensation
30amp model should be good for your needs

https://www.morningstarcorp.com/products/tristar-mppt/

plus your going to need the display meter

https://www.morningstarcorp.com/products/tristar-digital-meter-2/

Think I’ll give these a miss David man maths or not.

 

[sallylillian]

if you have an AES fridge with a S+terminal it tells the fridge to switch to 12v when batteries are charged and you have excess solar.

Yeh, but!

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[funflair]

Yeh, but!

It's OK Ken will have a proper old fridge like ours with just the D+ so if he does the fiddle with a diode then it will work in the correct sequence

Martin

 

[Lenny HB]

Yeh, but!

Not hard to mod to get it working properly.

 

[canopus]

Might need to discuss the fridge option with you Martin. At the moment I need to establish if my batteries are on the way out. Do I buy new ones plus an mppt controller plus any other necessary kit to give optimum performance.

I’ve definitely discounted AGM batteries.

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[funflair]

Might need to discuss the fridge option with you Martin. At the moment I need to establish if my batteries are on the way out. Do I buy new ones plus an mppt controller plus any other necessary kit to give optimum performance.

I’ve definitely discounted AGM batteries.

Give them a good charge on hook up, then the simple test of a known amp load and keep an eye on the voltage for how long they last then the maths is pretty simple,

120watts of bulbs will be 10amps, 10amps for 10 hours = 100ah so a 200ah bank should still be above 12 volts at the 10 hour point.

Martin

EDIT fridge is a 60 pence diode from Maplins inline with the D+ from the alternator preventing and signal going away to ground but still allowing the signal to come in.

 

[sallylillian]

It's OK Ken will have a proper old fridge like ours with just the D+ so if he does the fiddle with a diode then it will work in the correct sequence

Martin

Ah, oh for those steam versions!

 

[canopus]

Give them a good charge on hook up, then the simple test of a known amp load and keep an eye on the voltage for how long they last then the maths is pretty simple,

120watts of bulbs will be 10amps, 10amps for 10 hours = 100ah so a 200ah bank should still be above 12 volts at the 10 hour point.

Martin

I have purposely left the ehu off but the solar is still connected. Monitored the volts on the panel yesterday & overnight. The only load on the battery is from the CBE control panel i.e. display plus 2 indicator lights on the panel. In addition I switched the interior light on last night and this morning to write results down. Voltage dropped overnight as expected, but I think the acid test will be disconnect solar and then as you say a known load eg tv and see what the outcome is.

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[michael thorpe]

gel batteries are the type of batteries used in mobility scooters "they are not full of jelly?" they are lead acid but have a fibreglass filling between the plates inside the battery to hold the acid sill so it wont slop around and are sealed so they cannot be toped up or spill any acid if turned over, this type of battery is also called a "leisure battery" it is not designed to be an engine starter battery that gives a heavy discharge in one hit but to give a steady discharge over many hours down to about 30% remaining amp hours left in the battery if you try to take any more out of the battery it will "kill off the battery" as for a "lithium battery" forget all about them! you need a special "three stage" battery charger to recharge them and the price of the battery is nearly three time the cost of an AGM or GEL battery, both AGM or GEL use the same battery charger by the way,, it is a special charger so,, ""DO NOT TRY TO RECHARGE THEM USING A CAR BATTERY CHARGER"" the volts on a car battery charger are far to high to recharge an AGM or a GEL battery (max recharge volts are no more than 14.5 volt's for bulk charging and 13.5 volt's for float charge) a car charger could be pumping out 16+ volts!,, if your van is fitted with 80 amp hour batteries AGM or GEL and you change them to "normal car batteries" (lead acid) they type you can top up with (distilled water) you may need to change your battery charger inside the van as it wont fully recharge this type of battery but a normal car charger will be fine, and the new car type batteries will be half the price of AGM or GLE, but a word of warning,, you will not get the same length of user time out of car batteries as you must not knock the batteries out to more than 50-60% charge rate or the car batteries will go into ""supper discharge"" and they will not recover from that, no matter how long you re-charge them, so to slim that lot down,, you can replace your old batteries with AGM or GEL and get the same performance that your getting or go for the cheaper car batteries and change the battery charger but get a little less performance as a little less cost? DO NOT GO FOR LITHIUM BATTERIES!

 

[Urs4_2008]

gel batteries are the type of batteries used in mobility scooters "they are not full of jelly?" they are lead acid but have a fibreglass filling between the plates inside the battery to hold the acid sill so it wont slop around and are sealed so they cannot be toped up or spill any acid if turned over, this type of battery is also called a "leisure battery" it is not designed to be an engine starter battery that gives a heavy discharge in one hit but to give a steady discharge over many hours down to about 30% remaining amp hours left in the battery if you try to take any more out of the battery it will "kill off the battery" as for a "lithium battery" forget all about them! you need a special "three stage" battery charger to recharge them and the price of the battery is nearly three time the cost of an AGM or GEL battery, both AGM or GEL use the same battery charger by the way,, it is a special charger so,, ""DO NOT TRY TO RECHARGE THEM USING A CAR BATTERY CHARGER"" the volts on a car battery charger are far to high to recharge an AGM or a GEL battery (max recharge volts are no more than 14.5 volt's for bulk charging and 13.5 volt's for float charge) a car charger could be pumping out 16+ volts!,, if your van is fitted with 80 amp hour batteries AGM or GEL and you change them to "normal car batteries" (lead acid) they type you can top up with (distilled water) you may need to change your battery charger inside the van as it wont fully recharge this type of battery but a normal car charger will be fine, and the new car type batteries will be half the price of AGM or GLE, but a word of warning,, you will not get the same length of user time out of car batteries as you must not knock the batteries out to more than 50-60% charge rate or the car batteries will go into ""supper discharge"" and they will not recover from that, no matter how long you re-charge them, so to slim that lot down,, you can replace your old batteries with AGM or GEL and get the same performance that your getting or go for the cheaper car batteries and change the battery charger but get a little less performance as a little less cost? DO NOT GO FOR LITHIUM BATTERIES!

...
I think you confuse AGM (Absorbent glass mat) with GEL (Gelified ELectrolyte). https://en.wikipedia.org/wiki/VRLA_battery#Gel_battery

Lithium was invented in the 70s, and current leading battery technology in electric cars, phones, tablets, PCs, portable speakers, solar systems, clocks - almost everything we consume which is battery operated. About lithium in motorhomes:

Until now, mostly the most expensive motorhomes have been offered with lithium options, but now you also get it as options on the more normal motorhomes: Broken Link Removed

In a few years, my guess is that lead acid is something we all laugh about, how everything was so terrible "in the old days" - had to charge slow (charging lead acid to 100% takes many hours - 12-24 in many cases), heavy batteries, big, and relatively short lasting. Lower operating voltage on the lead acid, and you need a few batteries to be able to run a big inverter to power ie a microwave, coffee machine etc. Lifepo4 can draw really big currents with ease, even smaller batteries.


The most used lithium chemistry used in motorhomes use more like a two stage charge pattern: Constant voltage and constant current (CC/CV). Given you get a lifepo4 battery which is meant for 12v / motorhome / boat / leasure use, it's not strictly needed to replace every charging system you have onboard. But to get the famous fast charging that lithium supports, you need to do some other investments aswell, depending on what you have onboard. IE my solar charger (Victron Bluesolar MPPT 150/70) supports lithium charging, and tests reveal that I would get a hefty lot more power from my panels using lithium as a battery, as charging doesn't have to be limited to the little amount the lead acids supports. But my EBL stops at 20 amps and has no charge program optimized for lifepo4, so charging using this will take time (but faster than lead acid), but it works. Also, charging from the engine's generator currently goes through the EBL, meaning the same 20 amps limitation. There are combi-chargers which remedy this. Ie the Votronic Battery Charger VBCS 60/40/430 has a 60 amp DC DC lifepo4 charger which works fine with most modern motorhomes' generators, as well as 40 amp charging from the mains, and supports 430 watts solar system. There are different sized models for different needs.

I agree it's not as simple at slotting in any old (or rather new) lithium battery into your motorhome, but either if you read up about the subject and select a product that suits your needs (and you current charging system if you're not ready to upgrade), or go to a well known supplier and get help, if you want to go down the Lithium path.

In my latest motorhomes I've selected not to go for lithium mostly because of the price and how long I'm thinking of keeping the current motorhome before selling it. But I'm seriously dribbling on a lifepo4 battery at the moment.

 

[sallylillian]

...
I think you confuse AGM (Absorbent glass mat) with GEL (Gelified ELectrolyte). https://en.wikipedia.org/wiki/VRLA_battery#Gel_battery

Lithium was invented in the 70s, and current leading battery technology in electric cars, phones, tablets, PCs, portable speakers, solar systems, clocks - almost everything we consume which is battery operated. About lithium in motorhomes:

Until now, mostly the most expensive motorhomes have been offered with lithium options, but now you also get it as options on the more normal motorhomes: Broken Link Removed

In a few years, my guess is that lead acid is something we all laugh about, how everything was so terrible "in the old days" - had to charge slow (charging lead acid to 100% takes many hours - 12-24 in many cases), heavy batteries, big, and relatively short lasting. Lower operating voltage on the lead acid, and you need a few batteries to be able to run a big inverter to power ie a microwave, coffee machine etc. Lifepo4 can draw really big currents with ease, even smaller batteries.


The most used lithium chemistry used in motorhomes use more like a two stage charge pattern: Constant voltage and constant current (CC/CV). Given you get a lifepo4 battery which is meant for 12v / motorhome / boat / leasure use, it's not strictly needed to replace every charging system you have onboard. But to get the famous fast charging that lithium supports, you need to do some other investments aswell, depending on what you have onboard. IE my solar charger (Victron Bluesolar MPPT 150/70) supports lithium charging, and tests reveal that I would get a hefty lot more power from my panels using lithium as a battery, as charging doesn't have to be limited to the little amount the lead acids supports. But my EBL stops at 20 amps and has no charge program optimized for lifepo4, so charging using this will take time (but faster than lead acid), but it works. Also, charging from the engine's generator currently goes through the EBL, meaning the same 20 amps limitation. There are combi-chargers which remedy this. Ie the Votronic Battery Charger VBCS 60/40/430 has a 60 amp DC DC lifepo4 charger which works fine with most modern motorhomes' generators, as well as 40 amp charging from the mains, and supports 430 watts solar system. There are different sized models for different needs.

I agree it's not as simple at slotting in any old (or rather new) lithium battery into your motorhome, but either if you read up about the subject and select a product that suits your needs (and you current charging system if you're not ready to upgrade), or go to a well known supplier and get help, if you want to go down the Lithium path.

In my latest motorhomes I've selected not to go for lithium mostly because of the price and how long I'm thinking of keeping the current motorhome before selling it. But I'm seriously dribbling on a lifepo4 battery at the moment.

Thank you for spending the time correcting the @michael thorpe post. I was exasperated by the inaccuracy of its content which could confuse those seeking advice.

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[chaser]

Havnt read every post on this so apoligies if its already ben answered.
OK now i have agm leisure batterys but a wet engine battery so what do i set my solar to as it feeds both batterys, do i set it to gel and risk frying the engine battery or flooded and risk not charging the gels?

 

[canopus]

Update

Bought and fitted a Votronic MPPT controller, and ditched the 240v hook up. The leisure battery was full in no time at all, with some to spare judging by the illuminated AES led, all due to the very sunny day we had last week.

I’m now beginning to think that the ‘low volts alarm’ which gave me the scare originally was in fact just that. The battery now seems to be fully charged and stable. Charged the vacuum cleaner using the inverter and the volts were still at 12.7V after leaving the inverter on all day. I realise this is not very scientific, but for now normality seems to have returned, so will hold off purchasing new batts.

 

[Urs4_2008]

Havnt read every post on this so apoligies if its already ben answered.
OK now i have agm leisure batterys but a wet engine battery so what do i set my solar to as it feeds both batterys, do i set it to gel and risk frying the engine battery or flooded and risk not charging the gels?

@chaser Do you have GELs or AGM? It seems you state both.

What kind of solar charger do you have? If it has a "starter battery output" it's normally only a 2-4 amp trickle charge. Anyways, AGM and Wet batteries normally support 14.4 and 14.7 volts bulk mode, and 13.5-13.7 volts float (find documentation for your actual batteries). So if you have AGM leasure, and configure your charger for AGM, your wet starter battery supports even more volts (normally). Your problem could have been, if you have GEL house batteries, that the relative low voltage the GELs need could possibly have a very small negative effect on your wet starter battery charging. But in real life, not an issue. Meaning: Select AGM charge pattern (if you have AGM house).

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[canopus]

Currently have Deta GEL’s (3 x 140Ah) and new controller is set to GEL. Starter battery is new last summer and is no cause for concern.

 

[Saltings]

Old 110 amp lead acid battery although topped up and on constant charge with a CTEK MMS 5.0 it is not providing enough to power the fridge which works perfectly on EHU. So am changing to a 100 amp AGM which I have been advised will provide a higher voltage which will cure the fridge problem.
We also run PV cells (? Wattage) which early in the morning provide 19-20 amps building up to ca 25 amps later in the day. However the cells do not charge either battery (hab or motor) for some reason, even though we get a power reading at the controller for the cells, hab and motor battery.
Anyone got any views on this problem and also why we don't get a charge from the PV cells?
Cheers
Saltings

 

[Saltings]

Never thought about the controller and changing it to AGM! Another problem on the horizon...
Judging from what has been said there is no need to worry. Just set the controller to AGM and let it charge the Hab battery (AGM) and the motor battery (lead acid).
Controller is a SOLAR STCC 10.
If you have to change it to AGM:
1. How do you change this on the controller?
2. What will then be the effect on the lead acid (motor battery)?
Cheers
Saltings

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[Saltings]

Forgot to add re controller: correct spec is SOLAR STCC10, Solar Charge Controller.Spec 12/24v 10A RoHS.
Cheers
Saltings

 

[Lenny HB]

Old 110 amp lead acid battery although topped up and on cons. So am changing to a 100 amp AGM which I have been advised will provide a higher voltage which will cure the fridge problem.

What plonker told that load of BS. It is only the charging voltage that is higher.
Also how can you get 19-20 amps out of a 10 amp regulator, it's not possible.

 

[Saltings]

Naturally the people selling the battery!

So if the regulator only lets 10 amps out are you saying that replacing the present lead acid battery with an AGM battery will not help us to solve the problem with the fridge not being charged by the hab. battery?

Cheers,
Saltings

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[Lenny HB]

Naturally the people selling the battery!

So if the regulator only lets 10 amps out are you saying that replacing the present lead acid battery with an AGM battery will not help us to solve the problem with the fridge not being charged by the hab. battery?

Cheers,
Saltings

You don't say how much solar you have but I assume around 300 watts?
You regulator is a cheap 20 quid job and step would be to replace it with a decent MPPT regulator, I use a Votronic MPP 350 they are around £160 and they work very well, suitable for panels up to 350 watts a 250 watt one is only about £120.

The AGM's sold for Motorhome use are dual purpose batteries and generally give poor live the ones I had lasted 18months, I always use Gels now.

Is your fridge a 3 way or compressor one?.
If a compressor after sorting out your solar you would be best to replace the exsisting battery with a pair of flooded cells or Gels if you charger can charge them properly.

 

[Saltings]

Hi Lenny

The fridge/freezer is a Thetford 3000 which can run on EHU, 12V or gas, hence a 3 way.

This not charging when on the move is one of our biggest problems. No problem when using the EHU.

We only have room for one hab battery under the drivers seat so are restricted re size and number we can carry. (size is ca. 354 X 175 X 22).

Perhaps a single GEL is better than a single AGM?
Cheers
S

 

[Lenny HB]

Are you saying there is a fault either on your fridge or your electrics and the fridge is not running on 12v when driving?
Why can't you get a second battery under the other seat?

Providing your charger has a gel setting a gel would be a better option.

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