General How do you charge twin air battery

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General How do you charge twin air battery

@Pugglt Auld Jock Wow, what a life story!

Basically, what I was wanting was someone with real experience actually recharging the battery on a Panda TA using a suitable ‘smart’ charger who could tell me:

- precisely where to connect the negative clamp (constrained by the short clamp cable as shown in the pic)

or alternatively say

- “don’t worry, I just connected it to the place shown on the pic and everything was fine” (and Panda Nut has now given me that assurance 😊)

And now you’re saying don’t worry about keeping the battery connected to the car because: “on the Panda you can disconnect the leads with ‘gay abandon’ and loose nothing when it's reconnected”)

So it seems whichever I do will be fine (although the h/book does say you’ll need to reset the power steering, and the electric boot release, and the radio, and…)
 
@Pugglt Auld Jock Wow, what a life story!

Basically, what I was wanting was someone with real experience actually recharging the battery on a Panda TA using a suitable ‘smart’ charger who could tell me:

- precisely where to connect the negative clamp (constrained by the short clamp cable as shown in the pic)

or alternatively say

- “don’t worry, I just connected it to the place shown on the pic and everything was fine” (and Panda Nut has now given me that assurance 😊)

And now you’re saying don’t worry about keeping the battery connected to the car because: “on the Panda you can disconnect the leads with ‘gay abandon’ and loose nothing when it's reconnected”)

So it seems whichever I do will be fine (although the h/book does say you’ll need to reset the power steering, and the electric boot release, and the radio, and…)
OOps! I should have said I've no experience of the Twin Airs! They frighten me too much so I just tend to forget they exist. However the more mundane FIRE engined versions seem happy. I've had a few Pandas with this engine where I've removed the batteries and everything woke up again when reconnected. Same with my boy's 2014 Punto 1.4 8 valve. The body control module seems to remember everything including the radio code - as long as you've not fitted an after market radio of course. Maybe someone with more knowledge of the twin Airs could comment about them?

Edit. Where to connect the negative charger lead? I agree that probably no harm would come of connecting direct to the negative battery terminal when doing low current charging such as a DIY type charger puts out. Personally though I feel much happier connecting to a body or power unit earth. Constrained byt the short lead length? No reason why you shouldn't extend it. A jump lead would do this just fine?
 
Connection question (2016 TwinAir):
connect the positive (red) battery charger clamp to the positive (red) battery terminal (happy with that)
…and THEN
do you connect the negative (black) battery charger clamp to the negative battery terminal?????

Note: I have a recently purchased 5A ‘Smart Charger’ (Halfords) claimed to be suitable for stop start and all AGM/EFB car battery types up to 100Ah (the battery is 60Ah)

Observations
1. I’ve read on other forums (not Fiat) that the negative clamp should always be connected to a ground / earth point and NOT to the negative battery terminal itself because this can ‘fry’ the battery sensor
2. I’ve looked +looked but CANNOT find a suitable ground/earth alternative within reach of my clamp cable wiring
3. the only usable negative connection (within reach of the wiring of the charger clamps) that I can see is the small screwed bolt that secures the connector unit to the negative terminal (see pic)
The car handbook suggests otherwise... (see photo of it below)

The charging current is supposed to go though the smart sensor as information about the state of charge and battery health is stored in the car's 'body computer'. If you bypass this, it doesn't know that the battery has had additional charging and so may not operate the smart alternator appropriately and confuse the stop-start system -- that probably depends on how much 'extra' charge it gets since the car last ran.

Using your earlier photo, see the notes on it in yellow as this is clearer than the little drawing in the handbook
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Here's the whole page for the added info about waiting a minute after closing the drivers door before disconnecting the battery. To be honest, that would probably happen anyway :)
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Interrupting the power supply on modern vehicles is to be avoided if at all possible due to the problems which often result. Consequently I keep a 12 volt battery which I can connect in parallel with extension leads if I have to completely remove a lead from the installed battery, say when fitting a new one for instance. (mind you, on the Panda you can disconnect the leads with "gay abandon" and loose nothing when it's reconnected.)

In my younger days I would not have hesitated to hook my old transformer type charger up to my Mini or Cortina when I went to bed safe in the knowledge she would be ready for me starting her up in the morning. Now a days though that would be like playing Russian roulette. The problem, as many of you will know, lies with the electronic components on modern cars and their inability to survive voltage spikes and their associated currents. So where might these "spikes" come from? Well, with the traditional transformer type chargers - usually easily enough identified because they are heavy and bulky - What comes out on the battery connection leads is directly proportional to what goes in from the mains. So, a surge in supply at the plug on the wall results in a directly related surge in output at the battery terminals and if high enough something's going to go "pop"! That's where the Russian roulette comes in. As Dirty Harry said "Are you feeling lucky"? I have a couple of these old type chargers which I would now never connect directly to a fully wired up vehicle but do use to charge normal lead acid batteries, including EFB, on the workshop bench.

The "cure" is a modern "smart" charger which uses inverter technology ( get him eh? sound like he knows what he's talking about? ) and electronically monitors and controls the output so that mains "spikes" do not get through to the output side. Some where in the early 20's a number of the ancient vehicles in "the family fleet" just wore out from old age and had to be replaced with more modern ones which had a lot more electronics in them. Battery charging was just one of the areas for me to explore as I wanted to be able to charge without disconnecting battery leads. I did a lot of research and contacting manufacturers and , whilst most said they couldn't see any reason not to use their product without disconnecting the battery leads the only one who would guarantee it was CTEK (the even say so in their instruction sheets) So I bought a CTEK Multi XS 7000 and it's been used on a multitude of modern vehicles - My pal's Jaguar (I did sweat a little with that one but it was fine and it's been charged more than once) The local fireman's BMW and KIA, both my 2016 Ibiza and my 2023 Scala, my boy's Audi and other son's Punto and other vehicles, including a neighbour's Renault Twingo (weird vehicle I thought?) without ever disconnecting any battery leads. Several of the vehicle manuals recommend connecting the charger positive lead direct to the battery positive and charger negative to a dedicated earth point on the body or engine block/gearbox casing where no dedicated earth point is available. I believe this is so the battery monitor is included in circuit and can monitor battery state as it's charged? Who knows? but they say to do it so I do! In fact I always connect in that way now.

So the conclusion I've reached is that, as long as you use a decent "smart" charger and connect as mentioned above, there is pretty much zero risk involved in charging batteries still connected to their vehicle leads. I actually bought a "bargain" smart charger from Lidl/Aldi and monitored it with both ammeter and voltmeter while it charged one of my shop batteries. The output was rock steady and I've now used it a number of times on family vehicles when the CTEK has been being used elsewhere and it's never given me the slightest cause for concern - smaller output than the CTEK though so takes longer and does less by way of precharge checking and battery maintenance before commencing a charge. Unfortunately I lent the CTEK to a friend (I don't often lend my stuff) and it's come back only partially working. I've had it for many years so decided not to repair and bought a Ring RSC906 https://shop.ringautomotive.com/rsc906-6a-smart-battery-charger-maintainer.html to replace it. Had it a couple of months and so far all good. Used it to keep the shop batteries on top up and have used it on the Scala during my enforced rest when my hip was replaced and on the Panda - which doesn't see much other than shopping journeys.

Here's a picture of the CTEK sitting on top of one of my old transformer type chargers with the Lidl/Aldi jobbie in front on the kitchen worktop - Mrs J was out shopping at the time so Hush you all.

View attachment 456889

While we're talking about this sort of thing I'll offer a word or two concerning my "take" on jump starting modern vehicles. I notice my new Scala, and, in fact, the 2016 Ibiza she replaced, both showed in their owner's manuals that they could be jump started by connecting in the way stated above - So, jump vehicle battery positive to "dead" battery positive and jump vehicle negative to "dead vehicle dedicated earth point (on the VAG stuff this looks like a bright shiny bolt head fixed to the vehicle structure. I have to say that jumping modern vehicles is not to be undertaken lightly because the possibility of electrical "spikes" are very possible.

Traditionally, when jumping one vehicle to another, the red jump lead would be connected from the "good" battery positive terminal to the flat battery positive terminal and the black jump lead from "good" battery negative terminal to the flat battery negative terminal. There are many videos right now on you tube and others recommending exactly this. DON'T DO IT! If you absolutely must then at least do it like this: Red lead goes from good battery positive to flat battery positive and then connect the black lead from the engine block (or dedicated earth point) on one vehicle to a corresponding earth on the other. That way you are avoiding any possibility of a spark igniting battery gasses (hydrogen and oxygen) which is very possible especially if the vehicle with the flat battery has been "hammered" trying to start it. You're also including the battery monitoring sensor if you do it this way so are less likely to have problems with it if you do get the car going. The other bit of advice is, do not try to start the car immediately after making the connections. Let them sit connected for a few minutes during which the good battery will lift the flat battery voltage quite significantly (it's only a surface charge being induced in the plates but it reduces the differential non the less thereby making the leads work much less hard when you come to twist the key - this works particularly well if you have puny cheap leads) What you're trying to do is reduce the difference in voltage between the two. So, say four or five minutes later, try starting the vehicle with the flat battery. If the reason it didn't start in the first place is only because it's battery had insufficient charge then it's very likely it'll start. Now, having got it started, DON'T IMMEDIATELY REMOVE THE LEADS! Let the two vehicles run connected for a further few minutes - Maybe 5 minutes? During which the two batteries will more or less equalize voltages. This is important as the most "dangerous" bit for the vehicles is when you disconnect the jump leads (always negative - black - leads first.) and the regulating ECU gets to properly "see" the vehicle's battery. If there's going to be a spike this is probably the most likely moment so the less differential in voltage the better.

The trouble with jump staring one vehicle to another is that the electronics on both vehicles are interlinked. If you then start up the engine on the good vehicle, as many will do to stop the "good" battery being flattened by the "bad" battery, by turning that key you've just woken up all the electronics on that vehicle and added them into the mix. Then you twist the key on the vehicle with the "flat" battery thus allowing the entire miss matched hotch potch to communicate to any part of the system in both vehicles it decides to!!! It's a bit of a miracle that anyone gets away with it at all. I just won't do vehicle to vehicle jumps but I do jump start using a slave battery and have never had a problem.
My Aldi supplied version looks similar to the CTEK. It can be left connected and will stop charging when the battery is full. Has a lit display showing one two three or four bars and a voltage readout so fairly comprehensive. Its done good service for over 6 years now. When I bought it it was I think £19.99 so great value. Settings for different vehicle typres so you bave to remember to set it to car etc. or it goes nowhere fast. Its handy to see eactly where the battery level is at when its left connected. My spare seems to be a new battery and it charges to 14.2v It seems to hold the level to 13.9 thereafter.
 
The car handbook suggests otherwise... (see photo of it below)
yes indeed, but the Fiat h/book advice /guidance /instruction was explained in the OP, so the purpose of this thread was to examine the alternative (i.e. NOT following the h/book)
So thanks for the detailed response on this point but the Fiat h/book advice was never in doubt

The charging current is supposed to go though the smart sensor as information about the state of charge and battery health is stored in the car's 'body computer'. If you bypass this, it doesn't know that the battery has had additional charging and so may not operate the smart alternator appropriately and confuse the stop-start system -- that probably depends on how much 'extra' charge it gets since the car last ran.

yes indeed, which is why I raised this point in my “Observations” in my earlier post:

“1. I’ve read on other forums (not Fiat) that the negative clamp should always be connected to a ground / earth point and NOT to the negative battery terminal itself because this can ‘fry’ the battery sensor”, but your point seems slightly less alarming since I’ve also read that these systems “learn” from new data and, in effect, reset themselves to where they should be? (but I don’t know how long this would take, or how troublesome driving the car would be until that happened - assuming the reset would indeed happen).

However, as I mentioned above, the OP explained that the purpose of this thread was to examine the alternative (i.e. NOT following the h/book) in order (as the OP pointed out) to avoid these kinds of issues arising when the negative lead is disconnected:

So after charging you have to re-set the time/date, etc.
and would also include resetting the power steering, resetting the boot release mechanism (and maybe re-entering the radio codes?) as set out in the h/book (and there may be others in the h/book that I’ve missed)

So, the issue is not How to Disconnect the negative cable but rather how to avoid the consequences of disconnection which, since I’m probably going to need to do this quite regularly (my car usage is so low), it actually would become a significant +burdensome overhead and rather a convoluted process each +every time.

Fact is several members in this thread have said they have successfully recharged their batteries without disconnecting the battery +with no issues, but none had explained where they connected the negative clamp of the ‘smart’ charger, hence my further observations:

“2. I’ve looked +looked but CANNOT find a suitable ground/earth alternative within reach of my clamp cable wiring
3. the only usable negative connection (within reach of the wiring of the charger clamps) that I can see is the small screwed bolt that secures the connector unit to the negative terminal (see pic)”

I now have conflicting advice:
“Do what the h/book says or bad things may happen”
and
“If you do what the h/book says then bad things may still happen”
and
“Ignore the h/book - it’ll be fine”
☹️
 
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The primary reason for the idea of not connecting directly at the battery is that, when an 'old fashioned' wet and unsealed (removable caps on each cell) battery (rather than the modern gel-filled and spill-proof designs) is low on charge, the chemical reactions inside the battery liberate hydrogen gas which may be ignited by the spark from completing the circuit with jump leads or a charger. For the same reason, batteries should be charged out of doors.

Best point for connecting a negative is the lifting eye on the engine. But given you are only trickle charging it, and so not needing to get a huge current through, any exposed bit of metalwork will do. The one time mine was jumped teh recovery company clipped it to the metal of the inner wing by the bonnet hinge - yes, that's painted but the teeth of teh clip 'spiked' through that. Hasn't rusted - it's galvanised. (As an aside, I note in my 2020 Skoda there is a dedicated metal earth point on the inside of the front wing, specifically for connecting jump leads to -- that's not something I've seen before)

As to 'frying ' the sensor - the smart alternator gives out a much higher current and often (but briefly) higher voltage than a charger ever will - and that all goes through the sensor without issue....

Go back a stage though: does your battery need to be charged? Is it loosing charge and not starting? How old is it? Under 'normal use' of a few hundred miles a month it will last four or five years before becoming a problem. With your ultra low use, that may not be the case, but have you had an issue or is this for 'preventative' reasons?
 
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The primary reason for the idea of not connecting at the battery is that, when an 'old fashioned' wet and unsealed (rather than the modern gel and spill-proof designs) is low on charge, the chemical reactions inside the battery liberate hydrogen gas which may be ignited by the spark from completing the circuit with jump leads or a charger. For the same reason, batteries should be charged out of doors.

Go back a stage though: does your battery need to be charged? Is it loosing charge and not starting? How old is it? Under 'normal use' of a few hundred miles a month it will last four or five years before becoming a problem. With your ultra low use, that may not be the case, but have you had an issue or is this for 'preventative' reasons?
these points have already been covered, but I’ll just recap
- the battery is a modern ‘sealed’ heavy duty /high capacity stop start type (see pic)
- the battery is in good condition (Halfords checked with professional grade battery condition tester) so is not ‘old’ as in ‘end of life’ (I only bought the car in May with an itemised service history but no mention when the battery was replaced so, in view of Halfords test result, likely not more than 2 years ago)
- the battery was showing 85% charge when tested but the Halfords guy said this will certainly continue to drop during the winter months with my low usage
- this is, as you say, “for ‘preventative’ reasons” (I’ve always maintained my cars on this basis)
 
Thanks - the trouble with this forum is it can be troublesome on a phone to read back from the start.

Yes, I didn't say you had an old style battery, just that was the reason why that advice used to be given. No one seems to have updated teh advice even though batteries have moved on.

Everything you say there suggests you have no need to be charging the battery...
 
as of today, maybe, but we’re only in the first stages of winter and I don’t want this to be an ongoing concern (Halfords were quite clear that with my current usage and the extra demands of winter - heated front+rear screens, blower+ac demisting, heated door mirrors, headlights during the dark months etc etc the 85% will only continue to go down)
 
as of today, maybe, but we’re only in the first stages of winter and I don’t want this to be an ongoing concern (Halfords were quite clear that with my current usage and the extra demands of winter - heated front+rear screens, blower+ac demisting, heated door mirrors etc etc the 85% will only continue to go down)
...except none of those are used without the engine running, and so aren't affecting the battery (at least not so much as would make a difference).

Once the car has started, the alternator will provide all the power for those. (In fact, the heated screen will not operate unless the alternator is running with 'spare' capacity. if you press the switch too soon, the screen heater doesn't come on). Air con doesn't add any battery demand (the compressor is engine powered)... And the stop start system will disengage itself if the battery sensor suspects it's not up to it.

I really wouldn't worry.
 
...except none of those are used without the engine running, and so aren't affecting the battery (at least not so much as would make a difference).

Once the car has started, the alternator will provide all the power for those. (In fact, the heated screen will not operate unless the alternator is running with 'spare' capacity. if you press the switch too soon, the screen heater doesn't come on). Air con doesn't add any battery demand (the compressor is engine powered)... And the stop start system will disengage itself if the battery sensor suspects it's not up to it.

I really wouldn't worry.

in which case the battery should be at 100% not 85%
Let me put it another way, in the 7 months I’ve owned the car I’ve done less then 1,000 miles
 
in which case the battery should be at 100% not 85%
Let me put it another way, in the 7 months months I’ve owned the car I’ve done less then 1,000 miles
A lead acid battery's ability to be recharged decreases simply with time... it's a one way chemical decline. The 'condition test' essentially measures how degraded the chemistry is. Even if left completely un-used and disconnected, a battery will degrade. What is the date code on the battery (there should be a 'made on' date on the casing.

The battery's ability to hold its charge does diminish with falling temperatures but increases again once warmed.

Under a 1000 miles in seven months is not 'healthy' for a car... many parts of a car degrade through under use, not just the battery: the tyres will degrade as they are not rotating to load different parts of the casing through rolling and so develop stress cracks. The brake calipers will seize and the engine suffer from internal condensation, bearings will become stiff... and all those are more expensive things to attend to than a battery.
 
we seem to have wandered off the thread topic “How do you charge twin air battery”
It’s not about whether I should or should not be concerned about the state of charge of my battery, or about low usage (each journey averages 15-20 miles including a fast road section during which everything gets up to temperature) it’s about how to top up charge with a ‘smart’ charger without disconnecting the battery

Btw when I bought the car SS worked - now it doesn’t, a classic symptom of a battery not sufficiently charged (so I understand)
 
we seem to have wandered off the thread topic “How do you charge twin air battery”
It’s not about whether I should or should not be concerned about the state of charge of my battery, or about low usage (each journey averages 15-20 miles including a fast road section during which everything gets up to temperature) it’s about how to top up charge with a ‘smart’ charger without disconnecting the battery

Btw when I bought the car SS worked - now it doesn’t, a classic symptom of a battery not sufficiently charged (so I understand)
Stop start tends to stop working when a car is used mostly on short runs. The 'smart alternator' only delivers the full charge on long downhill sections or where the car is going downhill for long periods. If you don't get these in your regular drives it will disable itself.

Last from me here owing the thread drift :)
 
“thread drift” - that would be your posts
as I have already pointed out, this is all off topic
maybe others will be able to comment further / dispel some of the issues /concerns raised?

Note: forum threads here specifically link cessation of SS to low battery charge - the whole reason I am here
 
“thread drift” - that would be your posts
as I have already pointed out, this is all off topic
maybe others will be able to comment further / dispel some of the issues /concerns raised?

Note: forum threads here specifically link cessation of SS to low battery charge - the whole reason I am here
With the greatest of respect “thread drift” tends to happen with at least 50% of the topics on Fiat Forum, but it’s all part of the community and eventually getting to the solution of the problem. It’s easy enough to sift through the information supplied and take what you require and ignore the stuff which you deem not relevant. If you want a no nonsense diagnosis then you could take the car to a Fiat dealer and pay top dollar for the privilege. No need get peoples backs up, people that contribute on here are only trying to help…….unlike plenty of other car Forums about where you just get the sh*t ripped out of you for asking a quite sensible question
 
With the greatest of respect “thread drift” tends to happen with at least 50% of the topics on Fiat Forum, but it’s all part of the community and eventually getting to the solution of the problem. It’s easy enough to sift through the information supplied and take what you require and ignore the stuff which you deem not relevant. If you want a no nonsense diagnosis then you could take the car to a Fiat dealer and pay top dollar for the privilege. No need get peoples backs up, people that contribute on here are only trying to help…….unlike plenty of other car Forums about where you just get the sh*t ripped out of you for asking a quite sensible question
I agree that you shouldn’t “just get the sh*t ripped out of you for asking a quite sensible question” (which in my case concerned where to connect the negative terminal for a top up charge)

Being told in response that “you have no need to be charging the battery” at 85% isn’t helpful - I think that’s for me to decide?
 
as of today, maybe, but we’re only in the first stages of winter and I don’t want this to be an ongoing concern (Halfords were quite clear that with my current usage and the extra demands of winter - heated front+rear screens, blower+ac demisting, heated door mirrors, headlights during the dark months etc etc the 85% will only continue to go down)
Did they mention they sell batteries too ;) :ROFLMAO: !?
 
I'll add one more comment to help explain my earlier answer, and why I say don't charge it if it is at 85% charge. (Note that is different to 85% health)

A battery has two things that can be measured:
- the actual voltage (or how much charge is in it)
- and how 'worn out' the chemistry is ( how easily it will recharge, how high a current it can deliver, and how many more times it can be charged)

If Halfords tested it there should be two bits of information
- the state of charge or voltage (eg 12.6 volts)
- and the amount of life left (the health in percent).

After driving a few miles, the battery will be back at 100% charge, because the alternator (the generator) has topped it up as far as it can during a journey. That is shown by measuring its voltage, which should be 12.6V or more (with the engine turned off). A cheap (£10 or less) voltmeter can tell you this.

The battery health, or percent of life remaining is measured by assessing how much current (in amps) it can supply, and how well it responds to being charged up again (the charge acceptance). This declines over time and cannot be 'reversed' by being recharged again. The only way to get health back to 100% is to replace the battery.

You can see this on a phone: my iPhone always charges to 100% each night. But if I look at 'battery' under settings it shows the battery life remaining (the ‘maximum capacity’ or battery health) is 90%. It will always charge to 100%, but will last less long between charges as that health decreases. Recharging cannot reverse that decline in health.

Stop/start not working is a sign that the car's in-built battery monitor has detected that the battery health is not so good - and recharging won't help that.

And to confirm my other earlier answer (and that of several others who posted here): if you do feel the need to keep the battery voltage topped up, connecting the charger direct to the battery is fine as its a low-current top-up charger on a modern sealed battery.

The illustration below comes from the website of Varta, one of the leading names in car batteries. This shows that a battery at anything over 60% charge is OK, and is why I say don't recharge it in that case. The full article explains a bit more about the difference between charge and health - https://www.varta-automotive.com/en...icle-details/car-battery-testing-instructions

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