what size battery do I need?

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2nd Hand Yank
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Post by 2nd Hand Yank » Tue Apr 03, 2012 5:18 pm

sven '2' wrote:What the..?
Before I go around talking like a know it all. ;)

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pitrack_1
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For the original question...

Post by pitrack_1 » Tue Apr 03, 2012 10:27 pm

2nd Hand Yank wrote:My battery is a little knackered and I should probably replace it soon.

I know I could just check the service manual,
but I probably don't want to keep my EA82
plus I have 100W spotties and an auxillary electric radiator fan; both make the battery work harder.

Do I need a different or bigger battery to run a EJ22 or EJ25?

I'd prefer a leak-proof design if possible.
What's available?

I don't want to go too big though; prefer to avoid unneccessary weight.

Thanks
2nd Hand Yank,

(Zerothly, Some more info- with links- follows in another more detailed post.)

Firstly,
###More accessories- bigger battery and possibly bigger alternator.###

- The electrical demand is dependent on the battery when the engine's off.
- The electrical demand is dependent on the alternator when the engine's on (unless the alternator ain't working in which case it reverts to the battery).

For a newer engine with all the electronics, you'll get a bigger alternator. You'll need a bigger battery- more capacity to handle the larger demand AND probably more CCA to turn the bigger, maybe higher compression engine.

Secondly,
###Get a heat-tolerant battery/design, get a FRESH, charged battery (not one shelf stored for a long while). You may need to pay a lot of money###

You're in Townsville- a hot area. Hot for batteries being ambient is >20C. Then there's the under bonnet effect...And the main environmental killer of batteries is heat. (The actual main killer is misuse/abuse/neglect). Every 10C above 20/25C (depends on who you talk to) halves battery life.

- Antimony lead-acid battery technology is apparently heat tolerant and good for cycling.
- AGM (Absorbed Glass Mat) technology is good for jarring/vibrations but may not be as heat tolerant.

Century batteries are pushing their batteries' Aussie conditioning so they may be a good start for enquiries.

Thirdly,
###I'd suggest a bigger capacity (not CCA) battery until you replace your engine###

- More CCA simply means the battery can turn a larger motor. You current starter motor limits the current draw so more CCA won't help. CCA is calculated at -18C (0F).
- More Ah means the battery holds more energy giving you the reserve to run accessories overnight without depleting the battery for starting in the morning.

Hope this helps,
Patrick
Ex- 2010 Forester Diesel

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pitrack_1
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Post by pitrack_1 » Tue Apr 03, 2012 10:31 pm

Oh and the 2010 Forester Diesel alternator is rated at 170A. Lidsdale power station asked us to stand in whilst they did some maintenance, but I declined :-)
Patrick
Ex- 2010 Forester Diesel

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pitrack_1
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CCA, Ah, and other battery info

Post by pitrack_1 » Tue Apr 03, 2012 11:12 pm

SOME GOOD LINKS:
Car and Deep cycle Battery FAQ]
esp. The Car and Deep Cycle Battery Frequently Asked Questions (FAQ) 2012

Century Yuasalinks:
Different types of batteries and
Battery charging

DEFINITIONS:
- Cold cranking amperes (CCA) is a measure of RATE- How fast the battery can deliver its energy- that's how much current (read: starting grunt) the battery can supply at -18C (0F) for 30 secs. So a perfect fully charged 450CCA battery should supply 450A at >=12V for 30secs at -18°C/0°F.
- Ampere Hours (Ah) is a measure of the BATTERY electrical charge CAPACITY- How much the battery can actually deliver.That is, the TOTAL electrical charge (effectively energy) the battery can supply. This is measured when discharged at a specific rate at a specific temperature. Generally, this is the maximum current the battery can supply continuously for 10 hours at 20C. For example, if a fully charged battery can maintain a maximum 5A for 10 hrs continuously at 20C, it is rated at 5A x 10hrs = 50Ah. These values are seldom printed on car batteries.

TEMPERATURE
The main environmental effect is temperature. Here’s how things varies with temp:

#1 RULE: HEAT KILLS BATTERIES

Changes with temperature:
- Useful Capacity (Ah) increases with temp
- Useful Discharge Rate (CCA) increases with temp
- Evaporation increases with temp
- Plate sulfation increases with temp
- Plate degradation increases with temp
- Overall battery lifespan decreases with temp

OTHER FACTORS:
- Lead acid batteries are designed to operate at ~20-25C. Seldom is your vehicle’s battery at this temperature!
- Internal damage results from impacts, vibrations, overheating, overcharging, total/deep discharging sulfation, plate erosion. This reduces the battery capacity:
[indent] o Vibrations and impacts damage the plates. Bits break off reducing the plate size and therefore battery capacity. Broken bits can short a cell effectively negating it (removes ~2V, no capacity from that cell)
o Overheating, overcharging can evaporate the water. This concentrates the acid accelerating plate wear and reducing capacity.
o Overcharging can cause overheating, physical damage (warping) and battery explosions.
o Total discharging damages the battery permanently reducing its total capacity. The plates also ‘sulfate’ blocking current charge/discharge as the sulfates are non-conductive.
o Overcharging/discharging can cause excessive heat (accelerated plate wear), plate fracture and plate bending. Any touching and the cell is shorted.[/indent]
- Higher Temperatures accelerates the battery’s chemical reactions. This:
[indent] o Increases the amount of energy you can extract from the battery (effective Ah).
o Increases the rate at which you can extract the energy (effective CCA). This is why batteries tend to fail on cold days (lowers the CCA available)
o Accelerates plate damage. Apparently, you can expect to halve the battery life for every 10C over 20C.
o I.e. live fast, die young![/indent]
- CCA vs Ah: Think of this like a water tank with a pipe outlet:
[indent] o CCA is determined by internal plate area. Higher CCA = more plates in a give size = thinner plates = more fragile = possibly shorter life. It’s like the pipe diameter out of your water tank. Big pipe on small tank = quick empty.
o Ah is determined by the mass of Lead. Bigger battery = more Lead = more chemicals = more energy = more Ah. Like a bigger tank.
o Large CCA and small Ah (small battery size) simply means a small battery that can be drained quickly with possibly fragile plates.
o Smaller CCA = larger plates = probably more durable
o Larger battery = (in general) larger Ah = larger energy storage.[/indent]

OTHER THINGS:
- The lead acid battery is a high purity balanced chemical reaction. Keep it that way by avoiding contaminants and only used distilled/demineralised water to top it up.
- Impure water (such as tap water) can introduce salts that either produce gases (e.g chlorine), or salts that block the reaction and reduce battery capacity and lifespan.
- Batteries can be designed to protect against jarring/vibration, heat and other damaging effects. You just need to buy the right one.
- AGM (Absorbed Glass Mat) help protect against vibration/jarring.
- Deep discharge is anything below 12V, although with a supposedly charged battery the terminal voltage will be <12V if there’s a shorted/dead cell.
- Look at the links above for more info!

Hope this helps,
Patrick
Ex- 2010 Forester Diesel

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2nd Hand Yank
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Post by 2nd Hand Yank » Wed Apr 04, 2012 7:02 pm

Awesome pitrack! :)

I knew high CCA's by themself weren't the best thing. (small battery, high CCA's; fragile, short life)

It's funny that batteries are designed for cool temperatures even in Australia.
Thanks for the head's up.

I wonder if I need a battery with jarring protection. :confused:
I've done some severe bottoming and topping a few times. Could be why my battery isn't at its best atm... though it still does the job.

Perhaps just a battery with more lead would be robust enough,
if my cheap battery can live through my occaisional abuse. :p

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2nd Hand Yank
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Post by 2nd Hand Yank » Wed Apr 04, 2012 7:06 pm

pitrack_1 wrote:Oh and the 2010 Forester Diesel alternator is rated at 170A. Lidsdale power station asked us to stand in whilst they did some maintenance, but I declined :-)
ha ha ha. You might be able to arc-weld with that. :D

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taza
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Post by taza » Wed Apr 04, 2012 7:28 pm

pitrack_1 wrote:Oh and the 2010 Forester Diesel alternator is rated at 170A. Lidsdale power station asked us to stand in whilst they did some maintenance, but I declined :-)
Far out, thats really good. I think my 2001 Forester one is rated at 85A! Somewhere around there anyway.

I find if I turn my music up with my headlights on alone the lights dimm to the beats of the music. lol

If I crank up the spotties (x4), hi beams, air compressor and the stereo the car starts having a real hard time keeping up but this isn't often and it does the job ;)

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Battery codes and specs, Jarring protection, larger capacity and dead cells

Post by pitrack_1 » Wed Apr 04, 2012 9:58 pm

Here's another link: Bosch document listing battery codes and specs vs each other vs vehicle (plus other info).
2nd Hand Yank wrote:I wonder if I need a battery with jarring protection. :confused:
I've done some severe bottoming and topping a few times. Could be why my battery isn't at its best atm... though it still does the job.
You probably don't need it and temperature tolerance may be more a factor still... but if you do more dirt roads, corrugations, pot holes, bottoming out, bouncing, bumping, discharging overnight, high beams, driving lights, outings, mud, dirt, river crossings and general having fun with your vehicle and intend using it for a while yet, then my recommendation would be yes :cool:
2nd Hand Yank wrote: Perhaps just a battery with more lead would be robust enough,
if my cheap battery can live through my occaisional abuse. :p
I have found a larger capacity battery (more CCA and Ah) can allow the battery to start the car even with a dead cell. I upped my old Pulsar from a LM280BE (280CCA) to a AMF340 (340CCA) or now better (now 380CCA) and found even with a dropped cell (<11V) it would start the car- until another cell or something really died. This gave the reserve capacity (similar to the Ah capacity) upped from 45 to 75 mins. Provides a measure of safety and, of course, extended times between changes.

If it gets you from 2 to 3 years' life and costs less that 50% extra you're ahead of the $$$ game even without the hassle/worry factor. The money basically goes into the quality, workmanship and amount of Lead.

A cheap battery will work, just not as long. Think of it like a cheap spanner vs expensive name brand spanner.

Oh, and just check it's not the terminals, connectors and wiring that are failing and not the battery. Seen plenty of "my battery's dead" only to clean and tighten up the terminals or replace the terminal clamps/cables and she's apples.
Patrick
Ex- 2010 Forester Diesel

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Post by El_Freddo » Fri Apr 06, 2012 10:47 am

2nd Hand Yank wrote:I knew high CCA's by themself weren't the best thing. (small battery, high CCA's; fragile, short life)
You've missed the message that everyone's been saying in this thread. Our recommendations for higher CCA's isn't intended to remain with the standard size battery you're running at the moment, we've all been talking about upgrading the battery size to accommodate the larger capacity. If you get a larger capacity battery that's the standard size I can tell you that 95% of us here will walk away from such a unit - it just won't go the distance and won't hold up for the long run!

As another saying goes - "there's no replacement for displacement", same for batteries, but generally it's about size and weight.
2nd Hand Yank wrote:It's funny that batteries are designed for cool temperatures even in Australia.
It's probably an international common language designed to effectively communicate the battery's capabilities on a level playing field. Batteries aren't as effective when they're super hot all the time. If you're really worried about this you can make up a heat shield for your battery to deflect heat from it under the bonnet. I've thought about this but haven't got around to it yet.
2nd Hand Yank wrote:I wonder if I need a battery with jarring protection. :confused:
I've done some severe bottoming and topping a few times. Could be why my battery isn't at its best atm... though it still does the job.
The vibration they're referring to isn't the odd solid bump in the road - they're talking loads of km's on corrugated roads for hours on end - the kind of road that tries to shake your car to pieces if you're travelling at the wrong speed.
pitrack_1 wrote:I have found a larger capacity battery (more CCA and Ah) can allow the battery to start the car even with a dead cell. I upped my old Pulsar from a LM280BE (280CCA) to a AMF340 (340CCA) or now better (now 380CCA) and found even with a dropped cell (<11V) it would start the car- until another cell or something really died. This gave the reserve capacity (similar to the Ah capacity) upped from 45 to 75 mins. Provides a measure of safety and, of course, extended times between changes.
This is exactly what it's all about! Find a good brand of battery that makes a good product for what you want and is at a good price.

Some will say that you'll get 2 to 3 years out of a decent battery. If you don't let it run flat and NEVER run it below 10.5V (severe damage zone) you'll get more life that that. My wife's VT commo did 9 years on the factory battery! Even then it started the vehicle but it did funny things to the ECU's performance.
Then there was another issue. The bloody RACV guy told my wife it needed a new battery and before she could say "it's only 18 months old" he already had a new one in it and was gone! I was pissed at this, that battery had NOTHING wrong with it!

So what you need to do is go and visit your local battery specialist - and make sure it's not an autoblahn or a supercrap store! You might need to upgrade your terminals for the larger battery, correction, you WILL need to upgrade your terminals and get a bigger battery clamp ;)

All the best with the search - it shouldn't be too hard, the hardest part is working out which way around you need the +ive and -ive terminals...

Cheers

Bennie
"The lounge room is not a workshop..."
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sven '2'
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Post by sven '2' » Fri Apr 06, 2012 1:04 pm

Well said Bennie

I bought a new battery for the Ford yesterday.

Told him what the car is used for, we looked a prices, chose one (larger CCA), he fitted it, cleaned the terminals, threw in a $15 store voucher, all with a 2 year warranty.

In and out in 14 minutes.
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