How good are battery analysers.

Submitted: Wednesday, Dec 23, 2020 at 15:49
ThreadID: 140895 Views:2524 Replies:10 FollowUps:24
This Thread has been Archived
For the last 12 years I have only used flooded batteries under the bonnet.
I could easily test their capacity with a hydrometer.
Recently I replaced them with 2 Century Dual Purpose AGM’s each with a CCA of 760.
Next, I purchased an AE310 Battery Tester to set up my base line capacity for future reference and it showed the CCA of this battery at 32c as being 920 CCA.
This test doesn’t put a load on the battery and I can only assume it is measuring its internal resistance to approximate its CCA.
Does anyone know how these things work and how accurate are they?
Back Expand Un-Read 0 Moderator

Reply By: Dennis Ellery - Wednesday, Dec 23, 2020 at 17:06

Wednesday, Dec 23, 2020 at 17:06
I found the solution. After investigation, I have found that some testers inject a high-frequency AC signal into the battery to calculate its resistance. A common indication is that a 25% increase in resistance over the baseline indicates a performance drop from 100% to about 80%.
I have recorded the CCA and resistance baselines of my new batteries for future analysis.
If the resistance goes up 50% or the CCA rating drops 50% I shall replace the battery. If either happens before my 2 year warranty is up I will claim against the battery supplier.
AnswerID: 634496

Reply By: Member - pedro1 - Wednesday, Dec 23, 2020 at 18:40

Wednesday, Dec 23, 2020 at 18:40
I don't have much faith in the electronic testers, I had problems with a battery recently , took it back to the autoshop who had sold it to me and they tested it and said it was good. I disagreed so they kept it overnight and charged it fully and then retested it the next day . Once again it tested good. To prove the point I then reinstalled it and it won't turn the motor over, so the battery was replaced under warranty (1 year old ).
The autoshops are too reliant on these testers as well so if you you have a similar result get it checked by a non electronic method.
AnswerID: 634497

Follow Up By: Dennis Ellery - Wednesday, Dec 23, 2020 at 19:06

Wednesday, Dec 23, 2020 at 19:06
Thanks Pedro1.
There is not much I can do about it – the electronic tester cost $40.
A 1000 amp load tester will cost me $500 – if I was in business I would go this way.
0
FollowupID: 911728

Follow Up By: Member - pedro1 - Wednesday, Dec 23, 2020 at 19:35

Wednesday, Dec 23, 2020 at 19:35
Hi Dennis, The tester I was refering to probably isn't a $40 job either, but the one Century supply to the retail shops for warranty testing etc .
0
FollowupID: 911729

Reply By: StormCamper - Thursday, Dec 24, 2020 at 03:58

Thursday, Dec 24, 2020 at 03:58
I wouldn't have much faith in a hydrometer telling you the capacity of a flooded. A hydrometer only tells you the state of charge, whether they need to be equalised, & how balanced the 6 cells are relative to each other. My 155AH floorsweeper has a healthy reading on all cells yet at least 20% of it's original capacity is not available after a full charge.

My understanding is the AC impedance test is a rough ballpark number, more helpful to weed out a obvious bad battery, but it makes sense to get a baseline & watch it, id trust the AC test over those CCA tests.
Maybe do the DC resistance test with a powerful load? resting V - underload V / diff in amps.

TBH I never wasted time testing for AC impedance or CCA on starter battery. I just trust that a good brand will last & my true test is if it starts at say 50-70% charge then it's good. Good to oversize a bit too.
You soon learn the average lifespan of a particular battery & replace accordingly.

As for the "deep cycle" well you do a controlled constant current load test over 20hrs. But who has time for that? Is it really worth it if you sized for 50% or 30% DoD?
AnswerID: 634503

Follow Up By: Member - Jim S1 - Thursday, Dec 24, 2020 at 07:19

Thursday, Dec 24, 2020 at 07:19
With the deep cycle batteries I guess if you use a good battery monitor then knowing the real CCA gives more accurate readings for discharge and state of charge. From what I understand, few batteries are actually near their rated CCA, and that rating is constantly and gradually lowering.
You can do the 20hr test in, say, 10 hours and then adjust the figures, but as you say, it's all pretty fiddly.

Cheers
Jim
"Sometimes I sits and thinks, and sometimes I just sits." A fisherman.

"No road is long with good company." Traditional

Lifetime Member
My Profile  My Position  Send Message

1
FollowupID: 911733

Reply By: Gronk - Thursday, Dec 24, 2020 at 08:45

Thursday, Dec 24, 2020 at 08:45
Sometimes we can get too absorbed in needing to know more information about a thing that is designed to do a simple job.

I had a small van with 3 x 120 a/h AGM batteries in it. I knew when they were new, they would run the fridge for approx 3 full days.....from 12.9 to approx 12.3V.
After 5 yrs, the days went down to 2, so I knew the capacity had dropped, and if someone wanted to do a calculation , they could work out what % .

Point is, I didn't need to know how much capacity it had lost, as long as it still did the job it was bought for.
But , the batteries were only just lasting a weekends camping, so were getting close to needing replacement.
AnswerID: 634504

Follow Up By: Allan B (Sunshine Coast) - Thursday, Dec 24, 2020 at 09:45

Thursday, Dec 24, 2020 at 09:45
.
I agree with Gronk and StormCamper.

It is questionable that an AC impedance test to derive a CCA figure will provide any meaningful data. And in any case, how would you make use of such data? If the battery is performing its duty then all is well. If it fails to perform its duty then you would replace it. You are unlikely to replace it before it reached an unsatisfactory performance level unless it was in a critical performance duty.
It is possible that the readings obtained from a relatively inexpensive 'consumer' product could lead you into contemplating battery replacement earlier than necessary. After all if the beer is cold, everything is OK. lol

But maybe if you have time on your hands to be able to perform and ponder such data then it provides a feeling of satisfaction and security and fills in the Covid days.
Cheers
Allan

Member
My Profile  My Blog  My Position  Send Message

2
FollowupID: 911735

Follow Up By: Dennis Ellery - Thursday, Dec 24, 2020 at 11:28

Thursday, Dec 24, 2020 at 11:28
As the batteries are used both for starting and deep cycle and are connected together without an isolating relay – I like to have forewarning of trouble. I think if the resistance tests remain consistent as the batteries age it will be good enough for me. It won’t be the only test, I will do others like starting the 4WD around 12volt on a cold day, or starting with a single battery.
0
FollowupID: 911737

Reply By: HKB Electronics - Thursday, Dec 24, 2020 at 10:23

Thursday, Dec 24, 2020 at 10:23
I purchased a cheap smart battery tester off Ebay out of curiosity as it indicated it could test CCA, capacity etc. Looking at the thin leads compared to a carbon pile unit I thought how can it possibly do the job. Well to my surprise it does it quite well.

I had a Century Marine pro in the car as an aux for year, car went in for pre trip check and they indicated battery needed replacement, was looking ok on the voltmeter, whacked the tester on it and it showed CCA down and capacity around 50%. Did a discharge test and it and it came out about the same. The cranker in the car is an Optima around four years old, smart charger indicates it has problems as the voltage rapidly falls from 14.4V to less than 13V when the charger turns off and settles at around 12.6V. I tested the capacity about a year ago and it was around 60% but still starts the car fine. Just put the tester on it and it shows 780CCA, 50% charge, R=3.84m ohm. The Optima specs show new CCA as 830CCA.

Lifetime Member
My Profile  Send Message

AnswerID: 634505

Follow Up By: Dennis Ellery - Thursday, Dec 24, 2020 at 11:26

Thursday, Dec 24, 2020 at 11:26
Thanks, that’s useful information. I have 2 new identical batteries and their baseline tests are consistent. If I find someone with a carbon pile tester, I will check my smart tester against that.
As the batteries are used both for starting and deep cycle and are connected together without an isolating relay – I like to have forewarning of trouble. I think if the resistance tests remain consistent as the batteries age it will be good enough for me. It won’t be the only test, I will do others like starting the 4WD around 12volt on a cold day, or starting with a single battery.
0
FollowupID: 911736

Follow Up By: Allan B (Sunshine Coast) - Thursday, Dec 24, 2020 at 11:52

Thursday, Dec 24, 2020 at 11:52
.
Hi Dennis,

I appreciate your desire to have "forewarning of trouble." And the simplicity of your arrangement.
However, with the batteries directly coupled you do run the risk of over-discharging and not having sufficient power to start the engine. Incorporating an isolator relay would overcome this yet still provide a backup battery should the cranker catastrophically fail.

Do not entirely trust that testing will always protect you from disaster. I have experienced apparently good batteries suddenly failing with no warning signs or behaviour. One 4yo was performing well and starting without hesitation until it suddenly failed to the point of barely illuminating the interior light.
Cheers
Allan

Member
My Profile  My Blog  My Position  Send Message

0
FollowupID: 911738

Follow Up By: Dennis Ellery - Thursday, Dec 24, 2020 at 12:47

Thursday, Dec 24, 2020 at 12:47
Hi Allan, Thanks for the info.
In my earlier days, I used to have a starter and a deep cycle with an isolator between batteries.
I now have 2 x 90ah 2 x 760 CCA Dual purpose batteries – effectively 180ah with 1520 CCA.
I have voltage relays set to 12volt cut-off on the fridge outlets.
My theory regarding a deep cycle and isolated starter – if the starter malfunctions the deep cycle may not have the CCA to start, particularly if running fridges.
In the past, I have used Century Marine Pro – very tough batteries and never had a fault.
I now have Century Dual Purpose AGM – again tough batteries and I don’t expect a fault.
Nothing is guaranteed in life and the whole lot could go up in smoke tomorrow.
Merry Xmas to all, from us Sandgropers in the West.
2
FollowupID: 911739

Follow Up By: Allan B (Sunshine Coast) - Thursday, Dec 24, 2020 at 17:36

Thursday, Dec 24, 2020 at 17:36
.
I wasn't suggesting a deep cycle battery isolated from your starter battery Dennis. What I proposed was having an isolator between your two Dual Purpose batteries.

It's interesting that no system stands "head-and-shoulders" above all others. We each devise systems that we believe will best satisfy our needs. And maybe like me, keep changing the arrangement as time goes on, hoping to arrive at perfection. lol
Cheers
Allan

Member
My Profile  My Blog  My Position  Send Message

0
FollowupID: 911741

Follow Up By: Dennis Ellery - Thursday, Dec 24, 2020 at 18:08

Thursday, Dec 24, 2020 at 18:08
Hi Allan,
Your advice is appreciated, we both have different systems and different needs.
When I had a deep cycle battery separated by a relay – I wasn’t confident it would start my 4WD in an emergency. Its CCA was lower than the starter. It was running 2 Fridges and it was never up to full charge especially after a hot night. I wasn’t confident it would start my 4WD in an emergency.
The batteries I chose now are either Marine or AGM’s suitable for marine use, connected without an isolator. These have heavy-duty separators or glass mats between the plates to reduce the risk of internal shorts. I think these suit my purpose better than my old system.
Thanks for your interest
0
FollowupID: 911742

Follow Up By: Allan B (Sunshine Coast) - Thursday, Dec 24, 2020 at 19:06

Thursday, Dec 24, 2020 at 19:06
.
Actually Dennis, my needs are simply defined....... The battery system should be able to supply as much power as I need and to never let me down.
I suspect that your needs really are the same.

Oh, I nearly forgot....... And to keep the beer cold. lol
Cheers
Allan

Member
My Profile  My Blog  My Position  Send Message

3
FollowupID: 911743

Follow Up By: Batt's - Sunday, Dec 27, 2020 at 01:22

Sunday, Dec 27, 2020 at 01:22
Much simpler to have an isolator between them as mentioned and if one battery goes bad it could drain the other then your stuck. I had that issue back in 1990 with a 60 ser cruiser I knew nothing about dual batteries back then and the previous owner had the 2 x starter batteries connected together. I got a jump start drove straight to Mt Isa where I lived at that time and the auto elec fitted a solenoid relay between the 2 new batteries he fitted for me and I never had trouble again. A much safer set up especially for isolated areas where having a safe reliable system is important and I have never set one up again without a battery isolator.

Having a larger ah aux battery is usually the normal thing if you can fit one in so it's large enough to run your gear with some in reserve. These days solar panels are available in various types to extend stays and there's no reason why one can't be used for the starting battery as well if parking or camping up just to keep it topped up. I have a 110w panel on my ute's canopy permanently feeding the starter but I run a Waeco CDF11 off it sometimes as well. My neighbor has a Redarc battery isolator so when he has his portable solar panel on the aux battery it can top up the starter battery if it drops below a set voltage. It works well he has tried it at home first by turning on the headlights for a while gives you a bit of faith in knowing your car will start if parked up for a while camping it's a great basic set up very cheap relay cost like $80 online 5yrs ago. So there are other ways to set things up so you don't have to worry about getting a flat battery. We both have voltmeters on all batteries so it gives you visual piece of mind as well.
1
FollowupID: 911758

Follow Up By: Dennis Ellery - Sunday, Dec 27, 2020 at 09:28

Sunday, Dec 27, 2020 at 09:28
Hi Batts thanks for the info. A deep cycle battery has a lower cranking capacity than a starter. I wasn’t confident that after running 2 fridges overnight that the it would have the capacity to start my diesel.
The batteries are protected with voltage depend relays on the fridges. Marine batteries have heavy duty separators it minimise the risk of internal shorts. I carry a Lithium jump starter for emergencies. I get much better useable capacity, both for starting and deep cycle work, using 2 marine type dual purpose batteries close connected than a split system.
0
FollowupID: 911764

Follow Up By: Batt's - Sunday, Dec 27, 2020 at 14:32

Sunday, Dec 27, 2020 at 14:32
The supercharge allrounder I use is a calcium deep cycle/ cranking battery 105ah, 760cca so no loss in cranking power. The other good thing is with the solar connected the in cab voltmeter reads 13.1v in the morning I just checked it the car hasn't been started for 4 days under the carport, gets a few hours of sunlight on the solar panel in the afternoon each day.

Your batteries have plenty of cranking capacity not sure what your concerened about and why the need to have the gear to test them it won't help when they're flat you have a jump pack to help out, you bought a brand of battery your confident, comfortable with ? and are really happy with the battery set up you have ? I know I am with mine I'm chilled out and have no concers when I go to start my 4wd no matter where I am. Not having a go just my observation sometimes they die early sometime they exceed their expectations wait and see what happens or get something with a longer warranty may be.
0
FollowupID: 911770

Follow Up By: Dennis Ellery - Sunday, Dec 27, 2020 at 19:23

Sunday, Dec 27, 2020 at 19:23
Hi Batts I test batteries so as to replace them before they reach 50 percent. I dont wait till they die.
1
FollowupID: 911773

Reply By: Member -Pinko (NSW) - Thursday, Dec 24, 2020 at 10:51

Thursday, Dec 24, 2020 at 10:51
What a can of worms?
Imagine when we all have batteries on the back veranda to power our house overnight till the sun comes up in the morning?
Won't be cheap electricity then?
Living is a journey,it depends on where you go !
VKS 737 mobile 0049 selcall 0049

Member
My Profile  My Position  Send Message

AnswerID: 634506

Reply By: Member - shane r1 - Thursday, Dec 24, 2020 at 13:12

Thursday, Dec 24, 2020 at 13:12
The absolute most important comment/advice in this thread , thanks Allan B

“After all if the beer is cold, everything is OK. lol”

Cheers and merry Christmas and happy new year to all!
Shane
AnswerID: 634507

Follow Up By: Allan B (Sunshine Coast) - Thursday, Dec 24, 2020 at 17:01

Thursday, Dec 24, 2020 at 17:01
.
A very Merry Christmas to you Shane and to everyone. May your New Year be better than 2020.
Cheers
Allan

Member
My Profile  My Blog  My Position  Send Message

3
FollowupID: 911740

Reply By: qldcamper - Saturday, Dec 26, 2020 at 12:06

Saturday, Dec 26, 2020 at 12:06
They are a diagnostic tool.
They have their place in the market but definatly are not foolproof, and there are plenty of fools selling batteries these days.
They will give you information, it is up to you to decipher the data and act on what you think it means, just as you do with the carbon pile testers.
It is safer and more convenient to use the electronic version if your inexperienced with high discharge testers as they can destroy even a new battery very easily if used incorrectly.
Neither are very efficient on large batteries.

I agree with those that suggest the in situ method of gathering data.
AnswerID: 634520

Follow Up By: Dennis Ellery - Saturday, Dec 26, 2020 at 13:13

Saturday, Dec 26, 2020 at 13:13
Hi Qldcamper
I also have a Charge/Discharge meter.
I plug the Engle into this and let it run down the battery.
I then have amp hours (watts) consumed and the SOC shown by the voltage level.
This will give a good indication of battery capacity.
Cross-checked with the resistance from the Analyser.
The Discharge meter cost $36 and the Battery Analyser $35.
It amazes an old fellow like me, what’s available to test a battery these days.
0
FollowupID: 911749

Reply By: Kazza055 - Saturday, Dec 26, 2020 at 16:26

Saturday, Dec 26, 2020 at 16:26
I just purchased one of these - 12V Car Battery Monitor via Bluetooth 4.0 Voltage Meter Tester w/ auto Alarm BM2. I got $10 of the price so only cost me $22.99.

I am going to install it on the dual battery in the tub that runs the 2 fridges and now i will be able to monitor both the 60L Brass Monkey plus the battery voltage while sinking a tinny under the awning.
AnswerID: 634523

Follow Up By: Dennis Ellery - Saturday, Dec 26, 2020 at 16:53

Saturday, Dec 26, 2020 at 16:53
Thanks Kazza, looks interesting – How do you set the alarm volts?
0
FollowupID: 911751

Follow Up By: Kazza055 - Saturday, Dec 26, 2020 at 17:33

Saturday, Dec 26, 2020 at 17:33
Have no idea but will find out when it arrives.

My son has something similar in his camper and he can check the voltage remotely so I figured I could use it to monitor my battery in the tub.

That was the best deal I could find and then getting $10 off was a bonus.
1
FollowupID: 911752

Follow Up By: Dennis Ellery - Saturday, Dec 26, 2020 at 17:44

Saturday, Dec 26, 2020 at 17:44
Its not important Kazza - it will either be a button on the Monitor or a setting via the phone.
0
FollowupID: 911753

Follow Up By: Kazza055 - Saturday, Dec 26, 2020 at 18:36

Saturday, Dec 26, 2020 at 18:36
From what I can see there is only a red and black wire that connects to the battery so I would assume it would be d one via the app.
0
FollowupID: 911754

Follow Up By: Gronk - Sunday, Dec 27, 2020 at 07:39

Sunday, Dec 27, 2020 at 07:39
I monitor batteries with a small voltmeter. Once you know your batts, and the load, you can easily tell state of charge and capacity left.
2
FollowupID: 911759

Reply By: Allan B (Sunshine Coast) - Sunday, Dec 27, 2020 at 15:36

Sunday, Dec 27, 2020 at 15:36
.

Nothing like a good Battery Thread to finish up the Year. lol

Cheers
Allan

Member
My Profile  My Blog  My Position  Send Message

AnswerID: 634529

Follow Up By: Member - McLaren3030 - Sunday, Dec 27, 2020 at 19:17

Sunday, Dec 27, 2020 at 19:17
Either that or yet another rumour about what the 300 Series Landcruiser is likely to have as an engine etc. :-D

Macca.
Macca.

Lifetime Member
My Profile  My Position  Send Message

2
FollowupID: 911772

Follow Up By: Batt's - Monday, Dec 28, 2020 at 15:38

Monday, Dec 28, 2020 at 15:38
I heard it's all electric with a 550km range
2
FollowupID: 911774

Sponsored Links

Popular Products (12)