Will a battery with larger capacity cause damage?

Post by **Rattnalle** » 31 Jan 2019, 04:34

abscate wrote: ↑31 Jan 2019, 03:23 Wind chill has no effect on batteries, it is strictly the absolute temperature that determines performance

Wind chill is badly overhyped to tell eyeball views on the media.

Wind chill is relevant in survival guides for people who don't know what winter is like. What your media are doing with it I really don't get

IslandV70 · Post by **IslandV70** » 31 Jan 2019, 08:53

FYI:

: ahtemp.jpg (109.77 KiB) Viewed 900 times

Post by **xHeart** » 31 Jan 2019, 09:40

Chart helps.
This H6 battery in our 97' 850 says CA @32ºF 900 and CCA @0ºF 730. Is 900 & 730 an Amp value?
Per this chart, in my situation of temps @-20ºF. Would the CA drop to 400 and CCA to 300, respectively (ballpark)? Where will the voltage be -- 9.xxV?

: MVS_H6_2927.jpg (140.94 KiB) Viewed 898 times

Post by **SuperHerman** » 31 Jan 2019, 10:18

I am not sure if this applies to Volvo. On my newest 2016 XC90, the subject has not come up, so I don't know if Volvo has uses a similar system. My 2004 XC90, and prior S80 and XC70s did not. Newer Volvo owners should investigate their vehicles.

The only thing I want to add to this discussion is that some newer cars have a battery registration set up for a new battery install. I have this on all my BMWs post 2004. If a new battery is installed the type (AGM or Lead) and size CCA has to be programmed into the computer. The car has a "smart" charging system which monitors the age of the battery and other factors and changes the manner the battery is charged for optimal performance and life. The battery's CCA is a factor.

If your newer Volvo has this registration set up, then a battery replacement is not so simple.

EngineeringBloke · Post by **EngineeringBloke** » 31 Jan 2019, 10:38

CCA is a rating used in the battery industry to define a battery's ability to start an engine in cold temperatures. ... The rating refers to the number of amps a 12-volt battery can deliver at 0°F for 30 seconds while maintaining a voltage of at least 7.2 volts.

In CCA testing, a load is applied and the amps measured for upto 30 seconds or until the voltage drops too low. Even 7 volts should be enough to spin the starter, but, of course, when it is so cold, the oil in the engine will not be at its best, and there will be greater resistance to the engine turning over - driven by the serpentine belt and starter.

As the charge leaves the battery, the voltage will drop a little. When it is cold, it will drop more as the battery will not be able to provide so much charge.

Post by **mrbrian200** » 31 Jan 2019, 10:51

Charge rate and maximum voltage characteristics between AGM and standard lead acid are different. On a 2004 Volvo, the charging system is designed to work with standard lead acid batteries and you have to stick with that type of battery. An AGM gets overcharged by a system designed for standard, which shortens the AGM battery's usable life.

To answer your specific question: Generally no, the CCA rating doesn't make a difference beyond being able to turn the engine in colder temperatures.

The system on the BMW likely just modifies the maximum charge voltage based on a table of expected characteristics of an aging battery (the max charge voltage decreases with age) so that it isn't effectively overcharging an older battery that will no longer charge to the higher voltage that it would have when new (accelerating the battery's degradation). A good software based algorithm should be able to gauge these battery characteristics/condition regardless of age and without 'input' provided the battery technology matches what the software is designed to work with.

I don't know with 100% certainty, but I suspect the CEM software/LIN controlled charging systems on Volvos after around Y2K are more than likely one of these smarter software based systems. If it wasn't, there no way my sisters 2003 XC90 purchased a year ago would have still been operational with the original factory battery when she bought it @ 14 years old. We did replace the battery 'pronto' as the reserve capacity (key on engine off) had degraded to something around 10 minutes before voltage started dropping like a rock which would be an issue during winter weather.

IslandV70 · Post by **IslandV70** » 31 Jan 2019, 13:45

xHeart wrote: ↑31 Jan 2019, 09:40 Chart helps.
This H6 battery in our 97' 850 says CA @32ºF 900 and CCA @0ºF 730. Is 900 & 730 an Amp value?
Per this chart, in my situation of temps @-20ºF. Would the CA drop to 400 and CCA to 300, respectively (ballpark)? Where will the voltage be -- 9.xxV?

MVS_H6_2927.jpg

Yes - 900 amps at 32 degrees and 730 amps at 0 degrees. My quick calculation shows 480 amps at -20 degrees. At minus 20 you better have synthetic oil if you want it to start!
BTW - wind chill DOES NOT COUNT for oil and batteries, only people

okidiver · Post by **okidiver** » 01 Feb 2019, 06:29

Correct on the wind chill...it ONLY affects SKIN. OP, you can put a bigger battery in and relegate your battery cover to the garage somewhere--lots of us do it with no ill effects.

IslandV70 · Post by **IslandV70** » 01 Feb 2019, 07:40

Just FYI - my car with the standard OEM battery started no issues at all after sitting outside all night at 12 degrees F.

Post by **jimmy57** » 01 Feb 2019, 08:17

So that science is served well: Wind chill temp is not the actual temp of things as stated BUT wind blowing will cause greater heat transfer. So a vehicle parked outside for 10 hours at 20F with no wind may not have the engine block drop to 20F due to the mass of the block and fluids. With wind the temp of the engine throughout would reach 20F. A windy cold can produce starting issues that same temp doesn't create for that same vehicle if it is not windy. Wind is what you get when the cooling fan comes on..... There is an increased cooling and a true lower temp for anything that has a liquid that the wind can evaporate so don't open the hood and throw wet towels on your engine on a cold windy night.
If batteries cost and weight was the same for higher capacity batteries then carmakers would find that space and fit bigger ones. The charging system is fine with bigger. Your 1 A trickle charger may not like a weakened 1000 CCA battery. The weight, space, and cost all are penalties that have to be balanced in their decision. EPA testing weight classes affect the outcome of testing for emissions and for the window sticker and real world MPG.
The "smart" charging control on Volvos started in 2005 (2004 1/2 S40 and V50 had it too) and got a lot smarter with the intro of Battery Monitor Sensor(BMS) in 2011 on P3. Start/Stop and the intro of P5 (SPA) models gave it even more intelligence. Downside of BMS equipped vehicles is that you get notifications of electrical system issues long before you would notice anything and maybe some false alarms. That car that out of the blue wouldn't turn over one dy at the restaurant or that morning when you had to get the kids to the bus for the field trip, etc. etc., had a battery that the BMS fitted cars would have detected weeks earlier in most cases. Just give it a bit more time and your car will watch battery overnight and send you a text that your car's battery is weakening at accelerated rate.........(there probably is a car that already does this, I'm not sure)

Will a battery with larger capacity cause damage?

Re: Will a battery with larger capacity cause damage?