17 REG Astra K 1.4 turbo petrol auto stop start - Topping up Battery

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Tue 2 Mar 2021 00:04
17 REG Astra K 1.4 turbo petrol auto stop start - Topping up Battery - golfauto11

Hello,

My stop start has stopped working owing to battery suffering from low amount of driving and cold weather. I am getting a message up "low battery start car", which isn't a problem, it starts fine. I want to top up the battery, I only have an old trickle charger with hi/low setting. Is this suitable with the car having stop/start? Also, with the battery being in the boot, which is the best way of charging?

Thanks.

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Tue 2 Mar 2021 00:30
17 REG Astra K 1.4 turbo petrol auto stop start - Topping up Battery - elekie&a/c doctor
You need a modern smart battery charger suitable for a stop/start battery. You can connect a charger straight onto the battery ,or use the battery jump start posts in the engine bay . Info on the owners handbook .
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Tue 2 Mar 2021 00:33
17 REG Astra K 1.4 turbo petrol auto stop start - Topping up Battery - edlithgow

If I had a complicated car like that I'd disconnect the battery before charging.

This was recommended even for the last century Honda Accord I was driving for a while recently.

I havn't always bothered with my simpler 1986 car, which has no electronics other than a dash clock and the alternator (which did in fact fail, though probably unrelated.)

Not a specific stop-start consideration, just general electronic fragility concern.

Varta

batteryworld.varta-automotive.com/en-be/why-specia...p

seem to be pitching the special stop-start battery as heavier duty, akin to a traction battery.

I dunno what special characteristics a "modern smart charger suitable for a start-stop battery " has, if any,(but see below) but if you get one, it is very likely to have been Made in China and quite likely to be a POS. But you won't know this.

Re charging of stop-start, Varta don't say anything worth reading

batteryworld.varta-automotive.com/en-gb/charge-car...y

though re charging in general, they say

"For lead-acid batteries which are not maintenance-free, we recommend that you visit a workshop. Under no circumstances should you check the acid-water level yourself."

Ach so. Jawohl, mein Herr! (They are clearly full of it)

tontio.com/auto-guides/car-battery/stop-start-batt.../

"The AGM batteries sensitivity to overcharging must also be taken into consideration when recharging using a stand-alone charger. A car battery charger should be selected that has a mode switch for ‘AGM type batteries’ which limits the current to 20 percent of battery capacity at a charging voltage in the range of 2.4 volts to 2.465 volts per cell at 25°C/77°F.

I'm not quite sure what "limits the current to 20 percent of battery capacity" means, if anything, since current is measured in amps, while capacity is measured in amp-hours. I don't THINK the two are convertible without knowing the timebase, but apparently by convention they are rated at 20 hours, so an 80Ah battery charge/discharge current would be 4 amps, and 20% of that would be 0.8 amps.

batteryuniversity.com/learn/article/what_is_the_c_...e.

I wouldn't bet my charger (claimed to be AGM compatible) will hold to that but havn't had an opportunity/reason to test it on AGM. It certainly goes much higher on a conventional battery, and since there is no manual selection of battery type offered, it would have to sense the battery type. .

Not all stop-starts are AGM though.

Edited by edlithgow on 02/03/2021 at 13:33

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Tue 2 Mar 2021 19:01
17 REG Astra K 1.4 turbo petrol auto stop start - Topping up Battery - Bolt

I'm not quite sure what "limits the current to 20 percent of battery capacity" means, if anything,

Could be they are processor controlled, ie, they talk to the charger, it controls the charge rate as does the ECU when connected, but gather if the battery is disconnected they have to be reprogrammed to the ecu otherwise the alternator can overcharge the battery and kill it

I think thats the way it works but could be wrong?

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Wed 3 Mar 2021 00:58
17 REG Astra K 1.4 turbo petrol auto stop start - Topping up Battery - edlithgow

I'm not quite sure what "limits the current to 20 percent of battery capacity" means, if anything,

Could be they are processor controlled, ie, they talk to the charger, it controls the charge rate as does the ECU when connected, but gather if the battery is disconnected they have to be reprogrammed to the ecu otherwise the alternator can overcharge the battery and kill it

I think thats the way it works but could be wrong?

Well that might be what limits the current to means, in terms of how it does it. It doesn't really explain what 20 percent of battery capacity means in terms of current, which is unclear to me, for the reasons above. I THINK it might mean for a 20hr discharge, but if it does that seems to indicate a very low charging current, or my sum is wrong.

If you are correct, you can't practically disconnect for charging unless you have a (make specific?) fancy scan tool to reprogram the battery or pay someone that does.

New cars. Tortuous ordure.

The only thing that stops these threads being really depressing is that I don't have one, and aren't likely to.

Edited by edlithgow on 03/03/2021 at 04:36

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Tue 2 Mar 2021 19:42
17 REG Astra K 1.4 turbo petrol auto stop start - Topping up Battery - Galad

I always manually switch off the stop start function on my 2 year old Hyundai i30 petrol as my typical daily journey is 2 miles there and back for childminding (I'm retired) in an urban area. Am I correct that these devices are fitted to modern cars more to help meet emissions targets than promote fuel economy? I keep my cars for up to 10 years so would worry about excessive wear and tear on the starter motor from repeated stop-starts

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Tue 2 Mar 2021 20:17
17 REG Astra K 1.4 turbo petrol auto stop start - Topping up Battery - Bolt

I always manually switch off the stop start function on my 2 year old Hyundai i30 petrol as my typical daily journey is 2 miles there and back for childminding (I'm retired) in an urban area. Am I correct that these devices are fitted to modern cars more to help meet emissions targets than promote fuel economy? I keep my cars for up to 10 years so would worry about excessive wear and tear on the starter motor from repeated stop-starts

Bit of both really, SS if used does stop the engine so no emissions during the stop and no fuel used, though some say it causes more emissions on restart so defeats the object. Not sure if that was ever confirmed?

as for Starter motor, they were redesigned to take the stress of engine restarts without any damage or severe wear, but age is more likely to cause problems than its use, but someone else may know better.

apart from that system power will affect its working as a low battery or alternator not working properly can affect its use

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Wed 3 Mar 2021 01:10
17 REG Astra K 1.4 turbo petrol auto stop start - Topping up Battery - edlithgow

I always manually switch off the stop start function on my 2 year old Hyundai i30 petrol as my typical daily journey is 2 miles there and back for childminding (I'm retired) in an urban area. Am I correct that these devices are fitted to modern cars more to help meet emissions targets than promote fuel economy? I keep my cars for up to 10 years so would worry about excessive wear and tear on the starter motor from repeated stop-starts

That sounds like the usage pattern for which its optimised.

I'd also worry about the eye-watering price of (some) of the replacement batteries, and wonder if by turning it off I could get away with a standard replacement.

Probably in some cases the battery coding would prevent this.

I suppose the dedicated batteries (where fitted) are pretty heavy duty though and should last longer, especially if not used for stop-start..

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Wed 3 Mar 2021 13:43
17 REG Astra K 1.4 turbo petrol auto stop start - Topping up Battery - Bolt

Probably in some cases the battery coding would prevent this.

Not only batteries electronics in general, certain mobiles cannot have second hand or new components fitted without being recoded to the mobile chip

some even have a dedicated security chip to prevent repairs by anyone without the gear to code it-- becoming ridiculous imo now....

Some cars like Mercs are going that way or have?

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Wed 3 Mar 2021 14:00
17 REG Astra K 1.4 turbo petrol auto stop start - Topping up Battery - RT

Probably in some cases the battery coding would prevent this.

Not only batteries electronics in general, certain mobiles cannot have second hand or new components fitted without being recoded to the mobile chip

some even have a dedicated security chip to prevent repairs by anyone without the gear to code it-- becoming ridiculous imo now....

Some cars like Mercs are going that way or have?

In some cases, the Battery Management System can be fooled by simply changing the battery serial number by one digit, which makes the BMS realise it's a new battery - but that does need access to a diagnostic system for the car, eg VCDS for VW Group cars.

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