2.5V 100F Super Farah Capacitor Module 15V 16.6F Automotive Rectifier

Thread Starter

Technikal

Joined Jan 1, 2021
11
I am just making sure I have got the right understanding of what I hope to do and achieve.

My Car is a 2.0L Diesel ( Mondeo 2.0 , 2010 powershift )
My 3 Months old battery seems to struggle a bit in winter (1-1-2021) Due to only 5 mins drive to get to work and 5 mins to get back once finished for the day with maybe an extra 5 mins if I need to do a bit of shopping, I don’t feel the car battery is getting charged enough . Winter i do have heaters on , front and back winscreen heaters to remove ice . Heated seats on , Wipers on , Radio on and even lights on full on way back home.

The problem am facing. I have installed and android mirror with dash cam and sat nav that goes to sleep after 5 mins (stay on unless I switch it off manually, which i don't). This is installed with a permanent live from the fuse box (not sure which fuse as I did not fit it). When the battery is Low (shows voltage on dash) on starting the car in morning, the android mirror goes off and then comes back on after car is started. This only started happening in past month with less driving and cold start in morning and sometimes starting car to go back home.
The voltage shows about 12.3v in morning but once i start the car it drops to about 8V at times and 9V sometimes . at 8V the andriod mirror goes off and back on ( which is not good for it ) . Just incase i may want to see what it is.
https://www.ebay.co.uk/itm/12-1080P...921939?hash=item5b80dbf213:g:h2MAAOSwJ7RfpRtV

After much reading up and watching video of benefits of capacitors I decided to purchase
2-5V-100F-Super-Farah-Capacitor-Module-15V-16-6F-Automotive-Rectifier-12V.
eBay item number 392081001866

Specification:

Voltage: 12-16V
Capacity: 16.6-18F
Working temperature: -20-70°C
Volume: length 120* height 62*thickness 20MM

The main performance: Low ESR characteristics, high current can replace the battery.

advertised as Automotive Rectifier

Once i got this wired and connected to the car battery and left on all the time .
1. I am assuming the power amperage from this ( am estimating around 70 amps ? ) due to this item :
https://www.ebay.com/itm/2-Set-Supe...-16F-Engine-Starting-Cars-Truck-/264014147165
2. This will help the cold morning start up by supporting the battery with extra starting (cranking power) 70 amps (not full, but should help, without killing the capacitors) as the remaining amps will come from the battery.?
3. Will also help increase the car battery life and help with other car electrical stuff by keeping a stable voltage and power.?

Or am I missing something?
P.S i am still waiting for
2.5V 100F Super Farad Capacitor Module 15V
 

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Hymie

Joined Mar 30, 2018
982
I’m sorry to tell you that you have wasted your money buying the super capacitor – any gain from fitting it will be negligible/have no effect.

Cranking a car engine can easily draw over 100A from the battery – if we consider that the voltage drops to 10V, then at 100A the battery will be supplying 1,000J/s to the starter motor.

A super capacitor of 16F charged to 12V will be storing 1,152J – enough to crank the engine for about one second (if all the stored energy can be delivered to the starter motor). But if the battery voltage under cranking were to fall to 8V, then the energy drawn from the super capacitor (dropping from 12V to 8V) will be of the order of 130J, a minimal additional energy input.

To avoid the dash-cam switching off due to an excessive battery voltage drop during cranking – you could include a diode in its 12V supply and add a capacitor of say 4,700µF to maintain the voltage.

Unfortunately the only solution is to run the vehicle for a longer period between starts (to charge the battery) and/or reduce the vehicle electrical loads as much as possible.
 

Thread Starter

Technikal

Joined Jan 1, 2021
11
I’m sorry to tell you that you have wasted your money buying the super capacitor – any gain from fitting it will be negligible/have no effect.

Cranking a car engine can easily draw over 100A from the battery – if we consider that the voltage drops to 10V, then at 100A the battery will be supplying 1,000J/s to the starter motor.

A super capacitor of 16F charged to 12V will be storing 1,152J – enough to crank the engine for about one second (if all the stored energy can be delivered to the starter motor). But if the battery voltage under cranking were to fall to 8V, then the energy drawn from the super capacitor (dropping from 12V to 8V) will be of the order of 130J, a minimal additional energy input.

To avoid the dash-cam switching off due to an excessive battery voltage drop during cranking – you could include a diode in its 12V supply and add a capacitor of say 4,700µF to maintain the voltage.

Unfortunately the only solution is to run the vehicle for a longer period between starts (to charge the battery) and/or reduce the vehicle electrical loads as much as possible.
thanks for getting back to me .
i suppose fir this to work , one test to see if it will start car with no car battery connected to capacitors . from that i should get idea how good / bad the starting up is , if it can start the car . if it can , then good and should work better with car battery in parallel .
if it does not and or gets hot , than scrap the idea or get another one in parallel and try again .
 

Hymie

Joined Mar 30, 2018
982
OK, that would be a reasonable test of the super capacitor (to disconnect the battery and see if you can start the vehicle). Bear in mind that even if it starts the vehicle (which is extremely unlikely) the voltage drop is likely to wipe things like the radio code (due to the voltage discharging to zero) that will need to be reset.

I would be interested in you posting the results of your endeavours.
 

Thread Starter

Technikal

Joined Jan 1, 2021
11
OK, that would be a reasonable test of the super capacitor (to disconnect the battery and see if you can start the vehicle). Bear in mind that even if it starts the vehicle (which is extremely unlikely) the voltage drop is likely to wipe things like the radio code (due to the voltage discharging to zero) that will need to be reset.

I would be interested in you posting the results of your endeavours.
thanks . this being sold as a battery replacement , i spose its just a test which will confirm the description . which like you , i am thinking its not going to work ( start the car on its own ) .
further educationg myself , i should have gone for more expensive 2000f plus . but again , i just need that extra push to start only , after that the altarator is good. .
will replay back with finding after i het it and test.
 

lpalga

Joined Sep 4, 2012
1
You write that your car hsa a diesel engine. I presume that it has glow plugs that are turned on before trying to start the engine. Beware that some manufacturers do not light the lamp if the glowing time is short.
Each glow plug can draw up to 25 A when cold, dropping to about 4 A as they get warm.
I worked for an electronics manufacturer that pioneered MOSFETs for this application.
 

du00000001

Joined Nov 10, 2020
65
If you want to avoid driving just to charge the battery (might require a minimum of 10 minutes driving between starts): why not get a battery charger and put the car on the charger from time to time. As these chargers usually come with Amp meters, you would have an additional indication about the state of charge of the battery.

And no: neither does the supercap help much during starting (16 F = 16 As/V - little compared to the energy needs during start).
To minimize the energy waste by the "luxury devices", you could have the wiring altered - connecting these to some existing "Terminal 87" or installing an additional Term87 relay activated by Term15. This way they would be off when the ignition is off.
 

Thread Starter

Technikal

Joined Jan 1, 2021
11
Am still waiting for the super caps. After reading your comments and advise . i decided to just buy a better battery , so i got a
Varta F18 Silver Car Battery 12v 85Ah 800A Battery.
 

jpanhalt

Joined Jan 18, 2008
11,088
My largest implement engine is a 134 in^3 (about 2100 cc), 4-cylinder diesel. Its 12V battery is quite large -- about double the size in my car. For winter, I keep that battery on trickle charge (<$10 each). It also has a crankcase heater that I keep plugged in. Adding a heater might be a cheaper way to ensure it starts reliably.

One concern with a cold diesel is ensuring adequate oil circulation for the first few seconds after starting. Thus, there is a warning placard to set RPM >1300 when starting cold. If you use it daily, that is probably less of a concern.
 

Thread Starter

Technikal

Joined Jan 1, 2021
11
Thanks again. My other problem is i dont have a driveway or garage . its more trouble in the cold to trickle charge or keep the baterry warm . but yes if i did have a garage , i would do the same.
 

du00000001

Joined Nov 10, 2020
65
Thanks again. My other problem is i dont have a driveway or garage . its more trouble in the cold to trickle charge or keep the baterry warm . but yes if i did have a garage , i would do the same.
Looks like you have to make a "charging ride" from time to time.
No-load battery voltage is not a reasonable indication for the state-of-charge (SOC) of lead-acid batteries (unless the battery is already next to empty): it is around 12.5 V.
There are some "portable" units available that include a medium-sized battery plus a charger plus ? ? ? Some of these seem to be able to provide the current for at least 1 start - might be an option if you missed the other "SOC too low" indications.
 
If not too expensive buy several of the super capacitor banks and parallel them. If wanting to start an engine with they will need to add up to 2000F-3000F, or larger for a diesel. Might get a bit too expensive though. Also, keep in mind that all capacitors have leakage rates. So if you're not going to be running the vehicle for several days they might actually drain the battery a little. But I've seen people use super-capacitors to actually start vehicles and without batteries. However these vehicles usually have smaller 4 or 6 cylinder gasoline motors. The cars also needed to start within a few cranks :)

https://electronics.stackexchange.com/questions/221531/supercapacitors-as-car-batteries/221541

https://www.amazon.com/Maxwell-Dura...sprefix=super+capacitor+car+ba,aps,254&sr=8-5

Properly sized I imagine these can even be used to significantly lengthen the life of a starter battery used in your application.
Still for this sized project you might want to save yourself the time and expense and just use the diode and 4700uF capacitor solution proposed by Hymie above. Good Luck
 

LowQCab

Joined Nov 6, 2012
724
An additional ~10 to ~15 minutes of Engine warm-up time,
(morning and evening), will probably solve the problem,
and extend Engine Life Expectancy, and reduce the recommended Oil-Change frequency.
This is assuming that your Battery has not already been damaged by
being in a continuous state of partial discharge.
This also assumes that your Alternator has enough output to maintain no less than 14 Volts with
ALL normally used loads turned on.
This also assumes that your Battery Cables and Starter are in PERFECT working order.

A higher capacity Battery, and oversize Battery Cables are a good idea, but will not replace
the need for MORE than adequate Alternator Output.
The Alternator must be able to run all loads PLUS provide substantial Battery Charging Current.
Alternator Output must NEVER drop below 13.8 Volts under ANY circumstances.
Most cars are equipped with a "barely adequate" Alternator, ( in Current output capacity ),
and a Voltage Regulator setting that is too high to make up for it,
which can cause Battery overheating, or boiling, in hot climates.

Ideal Alternator Output Voltage varies according to the core temperature of the Battery,
and may vary by as much as ~2.5 Volts.

The Peak Current that a Lead-Acid Battery can deliver varies according to its core temperature.

Super Capacitors, in a car, are really only useful for Huge, High Power, Audio Systems.
Even then, a second Battery, ( preferably an AGM sealed type Battery ), is better in certain respects.
.
.
 

Thread Starter

Technikal

Joined Jan 1, 2021
11
An additional ~10 to ~15 minutes of Engine warm-up time,
(morning and evening), will probably solve the problem,
and extend Engine Life Expectancy, and reduce the recommended Oil-Change frequency.
This is assuming that your Battery has not already been damaged by
being in a continuous state of partial discharge.
This also assumes that your Alternator has enough output to maintain no less than 14 Volts with
ALL normally used loads turned on.
This also assumes that your Battery Cables and Starter are in PERFECT working order.

A higher capacity Battery, and oversize Battery Cables are a good idea, but will not replace
the need for MORE than adequate Alternator Output.
The Alternator must be able to run all loads PLUS provide substantial Battery Charging Current.
Alternator Output must NEVER drop below 13.8 Volts under ANY circumstances.
Most cars are equipped with a "barely adequate" Alternator, ( in Current output capacity ),
and a Voltage Regulator setting that is too high to make up for it,
which can cause Battery overheating, or boiling, in hot climates.

Ideal Alternator Output Voltage varies according to the core temperature of the Battery,
and may vary by as much as ~2.5 Volts.

The Peak Current that a Lead-Acid Battery can deliver varies according to its core temperature.

Super Capacitors, in a car, are really only useful for Huge, High Power, Audio Systems.
Even then, a second Battery, ( preferably an AGM sealed type Battery ), is better in certain respects.
.
.
Thanks for the info , Yes to all conditions that u mentioned above . extra 10 -15 mins before and after i agree is best solution for now.
 
Thanks for the info , Yes to all conditions that u mentioned above . extra 10 -15 mins before and after i agree is best solution for now.
Why not just put the capacitor after a diode from the battery (where ever the mirror is powered from now) then to the mirror. When you start the car, the capacitor will power the mirror until the battery voltage recovers. Likely you will need a 10-20 Amp diode.
 

Thread Starter

Technikal

Joined Jan 1, 2021
11
Why not just put the capacitor after a diode from the battery (where ever the mirror is powered from now) then to the mirror. When you start the car, the capacitor will power the mirror until the battery voltage recovers. Likely you will need a 10-20 Amp diode.
good idea , it should help instead of just wasting it
 

Hymie

Joined Mar 30, 2018
982
Whilst the peak current charging the capacitor may be 10A plus, it will be for a very short time – therefore a 2A or even a 1A diode may suffice since it is normally the (lack of) heat dissipation that kills a diode (or excessive reverse voltage). But check the diode’s spec. - a 1Amp 1N4001 can withstand 50A for a short time.
 

LowQCab

Joined Nov 6, 2012
724
That "Short-Time" is measured in single-digit Milli-Seconds, not minutes, and is a single "Non-Repetitive-Pulse".
The Mirror can probably run for several hours on a Capacitor that size,
that would be a massive waste of space and Money.
A 1000uf Cap and a 1N4001 will solve the Mirror drop-out problem,
but there are other, far more important problems that should be addressed first.
It's not "normal" for the Starting Voltage to drop that low in the first place.
.
.
 

MIS42N

Joined Jan 25, 2013
17
Have you got the biggest alternator and battery fitted? I see there's a 225 Amp alternator that fits some model of the Mondeo. You've identified the problem - not charging enough while driving. The solution would be charge more. That needs a bigger battery to handle the current without breaking down. You will not charge more by fitting capacitors, the battery will deteriorate if it's not getting enough charge, the capacitors just delay the point where the battery stops working. I don't like the idea of 'warming up' the engine - sludge condenses in the exhaust and 5 minutes driving may not blow it out. Best to drive off after a few seconds when the oil has had a chance to get pushed around. How long does it take to crank the engine? is there a problem there? my petrol car cranks for 0.7 seconds according to the mechanic (the printout from his automated electrical system tester), the alternator will put that back in the first 30 seconds of driving. I think you need to fix the cause of the problem rather than bandaiding the symptoms.
 
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