Interesting.
My car has a dashboard display showing amount of time the stop start system has been working and the amount of fuel saved. Usually only a few millilitres. Perhaps they could add another meter showing greenhouse emissions reductions?
BB
Itâs proportional to the fuel saved. One needs to make an assessment of the greater emissions created during a start sequence. This would include unburnt fuel and excess particulates not evident during normal running. Unlikely to be a constant ratio. I canât find a ready reference to how much extra. The base GHG emissions for an ICE based on raw fuel consumption are:
Nominally 2.3kg of CO2 /litre of gasoline, or 2.7kg of CO2 /litre of diesel.
My car is now 9 years old and still running happily on the original 12v car battery.
When it was brand new I installed Inox battery conditioner into the battery cells. The battery has unscrewable caps on each of the 6 cells so that water/inox etc can be added.
Inox battery conditioner is alleged to extend the life of lead/acid batteries by preventing sulphation of the cells.
Whether or not the inox does what it claims I have no way of being sure, but I am sure that 9 years and still going is an exceptional life for a car battery.
I am now looking around at new batteries as sooner or later my 9 years old battery will croak. But it seems that car batteries with unscrewable caps on the cells are a thing of the past. They are now all sealed so that I cannot install inox conditioner.
Whether this is a conspiracy by battery manufacturers to prevent people using inox, I do not know, but does anybody know where batteries with screw caps on the cells can still be bought from?
BB
Members are requested not to post or repost the same issues in new topics.
AGM batteries are totally unsuitable for under bonnet use.
AGM batteries are in fact deep cycle batteries and NOT vehicle starting batteries.
An AGM under the bonnet of a vehicle is totally unsuitable. An AGM battery is NOT a vehicle starting battery.
AGM are in fact a deep cycle battery for powering equipment.
AGM batteries are todayâs standard for vehicles with stop-start engine technology.
A simple search on AGM batteries for start-stop vehicles yields many hits, all alike. One of the many
and from a retailer, note the technology for the batteries listed.
Please refrain from posting misinformation.
Would you explain why that is so please.
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Never been able to have AGM batteries under the bonnet due to the heat. Reason why calcium batteries are never fully charged in a vehicle under the bonnet. If we could have fitted AGM batteries under the bonnet in defence/ambulance etc. vehicles would have made life much easier in a lot of cases. Common knowledge AGM batteries donât last. AGM batteries also need ambient temperature controlled charging for optimum capacity and longevity.
Do you have any data showing that in real world conditions AGM batteries in cars have a significantly shorter life in comparison to standard batteries?
They are often referred to as Absorbed Glass Mat batteries too. Noting that adsorption and absorption are two different processes, can anyone explain which they are and why both terms are in use?
A basic tutorial from a manufacturer.
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A substance thatâs adsorbed attaches itself to and stays at the surface of the other substance. A simple example is silver attaching to glass to form a mirror.
If itâs absorbed, it doesnât stay at the surface; it passes into the body of the other substance. Example: spilt liquid being mopped up by a paper towel.
If both terms are used with respect to the batteries, presumably both processes are involved.
I think the use of adsorbent in the case of AGM batteries is a typo or incorrect. The acid electrolyte wouldnât work if it just stuck to the surface of the glass matting. It has to be absorbed into the matting and charge free to flow between lead plates. Stops the acid sloshing around which can be an issue with flooded electrolyte traditional lead acid batteries.
If that were the case the process would be called properly be called sorbtion.
That article is informative but does not go into the low level chemistry.
Many people have never heard of adsorbtion and would assume it is a spelling mistake. I am none the wiser about whether it is one, the other or both in the case of these batteries.
Well, they are both a type of âsorbtionâ â but i suspect the average person would be just as confused by that term as by âadsorptionâ.
Maybe itâs neither. This is a fairly detailed explanation of VRLA batteries (of which AGM is one type)
⊠and it doesnât mention adsorption. But it also says the glass mats donât actually âabsorbâ the electrolyte ⊠
Maybe the author of the Wikipedia article doesnt have a good command of English spelling? Words like Robinson and Robertson are a good example of similar words which some people struggle with!
BTW is adsorbtion the same as electro plating?
A mirror can be coated with a film of aluminium or silver by putting it into an evacuated container and vaporising the aluminium or silver (in same container) using an electric current.
But I suspect electro plating may be a different type of bond.
BB
We are drifting away from car batteries but as you asked the short answer is no.
Electroplating is the formation of metal from metal ions in solution using electricity, a chemical change. The metal is deposited on the surface of an object. To silver plate a teaspoon the bare spoon (say of bronze) is made the electrode so the silver deposits there.
Adsorption is a kind of bonding where one substance bonds on to the surface of another. It doesnât require chemical changes to the substance bonding or the application of electricity. An example is ion exchange resin where the resin surface will bond metal ions (eg impurities) from water solution. The metal ions can be removed by cleaning with dilute acid, the hydrogen ions in the acid release the metal ions from the surface of the resin. This cycle can be done repeatedly, for example, to purify water.
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I just checked my bike battery and according to the users handbook, itâs an AGM battery and they spell it out âabsorbed glass mattingâ âb not dâ.
This from a brand and country that prides itself on technical excellence!!
Perhaps when inventing new words for new processes it might be a good idea 
to cook up a word that instead of sounding the same to unfamiliar ears and spelled ever so slightly differently, (adsorbed), cook up a new word altogether and avoid confusion 
BB
Just more BS â â â â we donât need. All the extra resources to make sensors and increase cost. Iâm sure all the extra engineering/components use many more resources than they save over the life of the vehicle. I.e: batteries and starter motors!!! But its all about âemissionsâ and fuel economy when selling a new vehicle. One of the biggest â â â â scams, at least in automotive. There are others i can go into lol
