AGM battery or should I have a leisure battery? (Ed.)

[ericmark]

The bit on my Lidi charger to say suitable for AGM batteries is in the manual.

The Ultimate Speed ULGD 3 8 A1 is a multi-stage car battery charger that is suitable for charging and trickle charging up of 6 V or 12 V lead-acid batteries (batteries) with electrolyte solution (WET), electrolyte absorbent mats (AGM) or gel electrolyte (GEL)

The Ultimate Speed ULGD 5.0 D2 is a multi-level car & motorcycle battery charger, which is suitable for charging and trickle charging 6 V (3 cells) or 12 V (6 cells) lead acid batteries (maintenance-free batteries (MF), open) with electrolyte solution (WET), with electrolyte absorbing mats (AGM), with gel gel-type electrolyte (GEL) or calcium batteries. The device is not suitable for charging lithium-ion batteries! You can also regenerate discharged batteries (depending on the battery type). The car & motorcycle battery charger has a safety circuit against sparking and overheating. Keep these instructions in a safe place. Ensure you hand over all documentation when passing the product on to anyone else.

It would be nice if it was written on the unit its self, but I have the 3.8 amp one in front of me, and it says nothing.

Most are stage chargers and it will have some thing like this

this one it says is 7 stage, but in real terms there are 5 charge rates, under 10.5 volt the pulse charge, in real terms this is normally skipped, it will charge at 5 amp until 12.8 volt, which is still quite a low state of charge, then at 3 amp until 14.1 volt, then 0.8 amp until 14.4 volt and it will then alternate between 0.1 amp and 0.8 amp. The latter Lidi charger shown here does seem to return to the 3 amp charge rate if voltage drops, the old one did not, and the old one would alternate off and 0.1 volt when set for a battery under 12 Ah. Not tested new one.

In the car the engine management controls the charge rate, but the big problem is the time taken to recharge. When something like a interior lamp has discharged a battery, I have used my energy monitor to see what is happening to the battery, and one can observe the mark/space ratio between 0.8 and 0.1 amp altering as it charges, the relatively new battery in the Jag when charged over Colvid would slowly increase the 0.1 amp time and decrease the 0.8 amp time until it would lift to 0.8 amp once a day. Always at same time, so clearly some thing in the Jag must turn on at that time.

But from when the LED display showed fully charged to when the 0.8 amp charge rate was just once a day, took some time, maybe a week, so this is the problem with lead acid, with batteries where one could top them up, we traditionally used a equalising charge once every couple of months, without this slowly the performance would drop off.

The was very evident with narrow boats, and owners would try to get a shore supply once a month to bring the batteries back up. All sorts if ideas were used to try and recharge the battery during the time the motor was running. Sterling made a alternator to battery unit which could pulse charge the battery and measure the decay rate to work out state of charge, with 3 x 140 Ah 12 volt lead acid they would start charging at 120 amp, but the problem is very soon after the rate has dropped to a few amp as the battery can't accept the charge fast.

Milk tankers and the like would use nickel iron batteries to be able to recharge fast. The vac pump would suck the milk in with engine stopped, and battery recharged while travelling to next farm, buses would also use nickel iron.

Sorry to say the battery charger shown is not suitable for AGM batteries, this one is, and states "Compatible batteries: Lead Acid, Wet, Gel, MF, EFB & AGM" however to recharge with a generator is not really going to work. My 3.2 kWh battery states maximum charge 2kW and maximum discharge 3 kW it is 50 volt and part of my solar system, and are very expensive to allow that charge and discharge rate, they are Lithium Iron Phosphate(LiFePO4) and need a special charger matched to the battery, and these can be charged in a couple of hours. But with lead acid of any type, looking at least 8 hours on charge every day.
In real terms you need more like 14 hours, milk floats, and fork lifts would need the batteries topping up quite a lot when recharging in 8 hours. What you are describing will not work for long. An inverter generator can still produce 230 volt at a tick over, so leaving running for 8 hours is not so bad, but non inverter to get 50 Hz need to run at a fixed speed, 6000 RPM divided by number of poles in the generator so 4 pole 3000 RPM and 6 pole 2000 RPM so even when only providing a few watt, it is still revving away.
So lead acid of any type does not seem to be what you need, only way to use lead acid is with solar panels or wind, as no one wants a generator running that long.

 

[ericmark]

he told me deep cycle and CCA makes no odds theses days

It will always make a difference, with flooded batteries the active material can be held on the plates well and the result is slow discharge rate, or use very thin separators allowing high current, it is true the AGM is able to do both, and is far better to the flooded, and he is likely correct in saying they are better for most traction systems, be it a stair lift, golf trolley, or mobility scooter.

However my e-bike uses a 48 volt lithium battery, which are far smaller and faster to charge. Wife's e-bike uses a 36 volt. I did my auto electrics training back in the 70's, and we did not have the lithium battery back then, my twin 18 volt battery hedge cutter and battery charger can use and recharge the batteries in an hour, so 4 batteries and I can works continuous. But even in 2000 when using battery drills to keep the job going we had to carefully plan drilling work as charge time was around 3 hours.

Can't say how to move forward, but battery and charging system are not compatible, so needs a serious rethink.

 

[Rodders53]

Second-user AGM battery would concern me. How many cycles has it done? What capacity does it have now?
(compared to a new battery of any type).
A battery man will have a proper tester of course, that can give some information/reassurance perhaps?

AGM has advantage over flooded wet lead acid leisure battery... spill proof/ any orientation operation.

You don't state brand of the AGM 019 but most are 3x the price paid for the better makes when new. Some of the cheaper leisure 110Ah batteries are really not up to much (despite the marketing bull).

Charging makes an enormous difference to the life of any lead acid battery - wet flooded, CaCa, Gel, VRLA etc.,. and I do not believe either of the chargers you have will be suitable for long term use, if you want maximum life from the battery.
The Lidl or Aldi smart chargers when available will suit the AGM recharging (snowflake mode on my Lidl iirc) and are cheap enough.

 

[JohnD]

I have a little Aldi smart charger, I think its max output is about 5A and it switches itself to "trickle" when the batt voltage is high enough.

I find it hard to believe that it could overcharge the huge 100AH type 019 battery. I could hardly lift it into place.

It is described as "wet" "calcium"
Not stop/start

 

[ericmark]

The Lidi one and Aldi one look very similar. The Lidi one says up to 120 Ah and odd same limit for the 3.8 amp and 5 amp versions. There are a few differences between them, and the new model is faster. But in both cases looking at days not hours to charge a fully discharged battery, even if it could charge at 5 amp, 120/5 = 24 hours, and it drops to 3 amp quite fast, so at least 40 hours in other words two days to recharge.

The big problem is once the supply is lost, it needs a button to be pressed to re-initiate the charging process. To top up the battery the main point is no need to keep checking it auto reduces charge I would move them around the three cars and batteries from caravan in turn when Colvid was on the go, as soon as one battery charged I would move it to next, however the charger we have at work, we can remove power and then plug back in and it starts to charge without needing to reset any controls. However at £260 it is not really what most people feel reasonable for a battery charger.

 

[AstonHill]

It will always make a difference, with flooded batteries the active material can be held on the plates well and the result is slow discharge rate, or use very thin separators allowing high current,

What are flooded batteries?

Can't say how to move forward, but battery and charging system are not compatible, so needs a serious rethink.

Are you saying that my chargers are no good?

 

[AstonHill]

Second-user AGM battery would concern me. How many cycles has it done? What capacity does it have now?
(compared to a new battery of any type).
A battery man will have a proper tester of course, that can give some information/reassurance perhaps?

AGM has advantage over flooded wet lead acid leisure battery... spill proof/ any orientation operation.

You don't state brand of the AGM 019 but most are 3x the price paid for the better makes when new.

Sorry its a Halfods

Charging makes an enormous difference to the life of any lead acid battery - wet flooded, CaCa, Gel, VRLA etc.,. and I do not believe either of the chargers you have will be suitable for long term use, if you want maximum life from the battery.
The Lidl or Aldi smart chargers when available will suit the AGM recharging (snowflake mode on my Lidl iirc) and are cheap enough.

But will my current 4amp charger work at all?
Do you know if they are in stock in Aldis/ lidal yet?

 

[ericmark]

What are flooded batteries?


Are you saying that my chargers are no good?

Flooded batteries are non AGM batteries, clearly until AGM there was no name for non AGM, and yes charger no good for AGM batteries.

 

[ericmark]

Sorry its a Halfods


But will my current 4amp charger work at all?
Do you know if they are in stock in Aldis/ lidal yet?

Yes but it will damage the battery, and although the Aldi/Lidi chargers are cheap, there are others, Ring, Durite, Ctek etc. A google for AGM battery chargers will find them this one for example but my point is the time it takes.

If you were charging it from a mains supply then leaving it for a week on charge is no problem, but if using a generator leaving the generator running for a week is going to cost a fortune.

Note the battery shown destroyed on the advert likely has a shorted cell, not a problem with battery charger.

 

[AstonHill]

Yes but it will damage the battery,

Will it over charge it?

and although the Aldi/Lidi chargers are cheap, there are others, Ring, Durite, Ctek etc. A google for AGM battery chargers will find them this one for example but my point is the time it takes.

That link there is an Amazon and dose not state in the title "AGM" simply "smart charger"
Will any smart charger do? like the ones seen hear

Argos 4amp 30 quid

https://www.argos.co.uk/product/4842721?istCompanyId=a74d8886-5df9-4baa-b776-166b3bf9111c&istFeedId=30f62ea9-9626-4cac-97c8-9ff3921f8558&istItemId=rxtaixiwt&istBid=t&&cmpid=GS001&_$ja=tsid:59157%7Cacid:804-872-0397%7Ccid:20330964438%7Cagid:%7Ctid:%7Ccrid:%7Cnw:x%7Crnd:2381448921650200891%7Cdvc:c%7Cadp:%7Cmt:%7Cloc:1006912&utm_source=Google&utm_medium=cpc&utm_campaign=20330964438&utm_term=4842721&utm_content=shopping&utm_custom1=&utm_custom2=804-872-0397&GPDP=true&gad_source=1&gclid=Cj0KCQiAnrOtBhDIARIsAFsSe52bb-o-Y1y9J6PAgnMIkZhPpoIthXP5k_5JyTEbmr4iAf9l0cOLXrQaAvfBEALw_wcB&gclsrc=aw.ds

Euro car parts, Ring 6amp 40 quid

Ring 6A Smart Charger and Battery Maintainer RSC806 | Euro Car Parts

Ring 6A Smart Charger and Battery Maintainer RSC806 at the lowest UK prices from Euro Car Parts UK’s No.1 for Car Accessories, Car Styling & Car Care. Buy today Online, In store or by Phone + Branches Nationwide – Next Day UK Free Delivery.

www.eurocarparts.com

Euro car parts Ring 4amp 30 quid

Ring 4A Smart Charger and Battery Maintainer RSC804 | Euro Car Parts

Ring 4A Smart Charger and Battery Maintainer RSC804 at the lowest UK prices from Euro Car Parts UK’s No.1 for Car Accessories, Car Styling & Car Care. Buy today Online, In store or by Phone + Branches Nationwide – Next Day UK Free Delivery.

www.eurocarparts.com

Tool Station Drapper 4amp 37 1/2 quid

Draper 12V/4A Smart Charger and Battery Maintainer

• Charge type: automatic smart charger/maintainer• Charge rate: 4A• Voltage: 6V/12V• Suitable battery type: WET, MF, Ca/Ca, AGM, GEL, LiFePO4• Dimensions: 165 x 75 x 48mm• Weight: 0.6kgThis Draper portable 4A smart charger does more than just charge 6V and 12V vehicle batteries. It has the...

www.toolstation.com

Screw Fix RAC 4amp 38 quid

RAC HP239 0.8-4A Smart Battery Charger 6 / 12V - Screwfix

Order online at Screwfix.com. Suitable for 6 and 12V car and motorcycle batteries with petrol/diesel engines of up to 3Ltr. Protected against reverse polarity, short circuit and thermal overload. 5-stage intelligent charging can be used with wet, gel, AGM and maintenance-free lead-acid...

www.screwfix.com

Halfords 4amp 32 quid

Halfords Smart Battery Charger 4A | Halfords UK

Shop the latest at Halfords UK

www.halfords.com

This one at B&Q dose not say its smart! is it no good?

GADLANE Automatic Battery Charger 12V/24V 10Amp | DIY at B&Q

GADLANE Car Battery Charger - 12V/24V automatic battery charger for cars, trucks, motorbikes, & boats. 7-stage charging process and intelligent charging modes. Highly efficient (>85%) and ideal for AGM and LiFePO4 batteries. Illuminated LCD screen to monitor the charging process. Built-in fan...

www.diy.com

 

[AstonHill]

Flooded batteries are non AGM batteries, clearly until AGM there was no name for non AGM, and yes charger no good for AGM batteries.

I presume flooded means flooded with lead acid then

 

[bernardgreen]

Sulphuric acid.

 

[ericmark]

I have found it with the 7 Ah batteries used in intruder alarms, and stair lifts where one stair lift the batteries can last 10 years, and another one they need changing every 2 years. There are cases of faults developing in batteries so it is hard to say the charger was responsible for all short lived batteries, but items like milk floats could run 25 years on a set of traction batteries, so treated well a traction or AGM battery can last a very long time. The traction is a flooded and AGM sealed, so different chargers, however both used stage chargers.

The battery when fully discharged can accept a large amount of power, but as it nears fully charged high charge rates will damage the battery, so the battery charger uses a fixed voltage or current, and measures the other, so it knows when the battery is around 80% charged and reduces the charge rate, not a perfect system, in the narrow boat the 3 x 140 Ah batteries were charged with a three stage charger, and to switch to final stage it measured the current and when it dropped to around 6 amp it reduced the charge voltage.

However this relied on the batteries being correctly sized for the charger, and no power being used while on charge, so turn on the tunnel lights and they used 5 amp or so, therefore the charger would not reduce charge.

So we have the pulse charger which gives a pulse, and then measures the voltage decay to assess charge state, these can charge the battery much faster, and are used a lot on narrow boats, and also solar and wind chargers.

Putting a 90 Ah battery on a 0.2 amp charger will in the fullness of time charge it without doing any damage assuming voltage limited to 14.8 volt max, but 90/0.2 = 450 hours, and we tend to want to charge the battery faster, so the whole thing is down to the speed required. I had two 35 Ah AGM batteries on a mobility scooter, the charger was only 6 amp, but a cell went short circuit in one of the pair, so the charger did not auto turn off, and the good battery destroyed due to over charging as charger did not switch off. So even at 6 amp the charger can kill an AGM battery.

The charger I linked to said

12V 6A Battery Charger: Suitable for most types of lead-acid batteries, including calcium, gel and AGM, wet, etc. (NOT for lithium battery). Great for 12V car, motorcycle, pickup, steamboat, ATV, engineering vehicle and more.

I was careful to select one which says AGM.

But it is the speed which is likely the problem using a generator, you don't want the generator running for 18 hours to charge the battery.

 

[cdbe]

Personally I think you need to go back to square one on this. I know you have bits and pieces but if you're living off grid full time and want to be comfortable you need a slightly more designed system with adequate capacity. As you're (presumably) all year round then solar is only suitable as a "fuel saver" in the summer. You need to do a power audit, be aware that lead acid are probably still the cheapest battery power available, and aim (for long term life) for a maximum 25% discharge - so with a bit of leeway probably take 30 amps from a 110amp battery and then recharge it - you really need to nurse them like children!. As you have a genny, find out the maximum output and match your charger's input to this. Then take the chargers's output and see how long it will take to replenish your battery(s). You then have choices - bigger genny, bigger battery, more batteries, running the genny for more or less time etc etc.

In other words sit down and do some maths. Assuming your batteries and other equipment is all serviceable it's fairly scientific. The main issue you're likely to face, if it turns out you need 2 or 3 batteries to meet your needs, is that you'll want to connect them in parallel (to give you essentially one giant long lasting battery) and there are a few precautions required when doing this.

If your genny is running off petrol maybe look at diesel or LPG - again do the maths.

Before this off grid malarkey became fashionable I used to pick up ex UPS batteries off eBay for next to nothing - usually they'd only been cycled a few times and were just time expired - but gave me good service for as long as 10.years.

 

[ericmark]

I do like what @cdbe says, when my son lived in a narrow boat (also an electrical engineer) we would have at times some heated debates as to best methods within price range.

He had 4 x 140 Ah batteries, one reserved for engine, and 3 for domestic, what we ended up doing was either once a month finding a shore supply so 48 hours on charge, or swapping which of the 4 used for engine, as on the engine it could be fully charged, but on domestic he did not Cruse for enough hours to fully recharge them.

Both the engine and shore chargers had separate charging for engine and domestic, engine actually had two alternators, domestic were stage charged and engine float charged. A typical charge controller uses PMW or MPPT charge technology, and to be frank these all came out after I trained as an auto electrician, so not sure exactly what they do, I think the MPPT is claimed to be better, but they are fighting with three variables, one amount of sun, two domestic load, and three charge rate. It is quite a balancing act, and to add to it using AGM batteries would not be my selection.

If one is prepared to throw money at it, then there are ways, but in the main, we try to get away with spending as little as possible, and so some luck comes into the equation, on the Falklands with off grid living we managed to buy an old bus, so had some Nickel Iron batteries and a good green house.

The Nickel Iron battery is reverse of lead acid, and they are better stored discharged, so it did not matter if never fully charged, they can also charge and discharge faster, the new range of Nickel, Cad, and metal halide batteries has seen the demise of the old Nickel Iron, but with alkaline batteries cost is far higher, and chargers are rather special.

I would say for off grid living best idea is to go onto a canal boat forum, where they are use to living off grid, it is a specialist subject. once you have learnt it, we can pick your brains.