Are there things to watch out for buying a 100ah battery?

Hi battery gurus...

Is there any issue buying a second hand battery (3.5 years old), they are the following brand:

http://www.solarguru.com.au/PDFs/6FM100HX.pdf

If not those specifically, is there anything to look out for as pros OR cons of different batteries?

Thanks as always.

Back Expand Un-Read 0 Moderator

Reply By: Richard Kovac - Tuesday, Nov 17, 2009 at 23:28

Tuesday, Nov 17, 2009 at 23:28
Lia

Yes if it has not been used, if not it will/maybe OK. I don't know what a battery self life is, (will read info).

If you want to insert a link... just copy and paste address into (see bottom of follow up box) Insert Link. Lia H

click insert link box paste address and name it if you like then press insert

hope this helps

Cheers

Richard
AnswerID: 391568

Follow Up By: Richard Kovac - Tuesday, Nov 17, 2009 at 23:36

Tuesday, Nov 17, 2009 at 23:36
I got my answer back to front.. LOL

If the battery is 3 years old and not used and second hand it should be OK, as said I don't know what a battery self life is.

If its been used, then you are buying a second hand battery, unknown...

the one the PDF was designed for a 10 year life span...

did this come with the CT?

Richard
0
FollowupID: 659461

Reply By: guzzi - Wednesday, Nov 18, 2009 at 07:43

Wednesday, Nov 18, 2009 at 07:43
How much are they asking?
If its been kept fully charged and not drained below 12V on a regular basis it "should" be OK. I have a 5 yr old AGM battery on the camper and it still does the job.
What are you wanting to run off it?

Pete
AnswerID: 391581

Reply By: Member - Mike DID - Wednesday, Nov 18, 2009 at 07:55

Wednesday, Nov 18, 2009 at 07:55
I would NEVER buy an old battery without doing a discharge test on it to see what its actual capacity is.
AnswerID: 391583

Follow Up By: redeye141 - Wednesday, Nov 18, 2009 at 18:08

Wednesday, Nov 18, 2009 at 18:08
Every battery should be charged every six months when on the shelf. If there is no audit trail of this happening I would offer $0 for it.
being idle will drematically reduce the battery life when no charging either float or periodically occurs.

Garry
0
FollowupID: 659569

Reply By: Maîneÿ . . .- Wednesday, Nov 18, 2009 at 08:42

Wednesday, Nov 18, 2009 at 08:42
Lia,
As Mike says, ask them if they will allow you to take it to a battery reseller, have them do a deep discharge test on it to see how it holds up.

Do you know why it is being sold ?? (assuming it's a private sale)
You say " second hand battery, *they are* the following brand"
( plural - are there more than one? )


It's a well designed Deep Cycle battery, not a basic compromise that promises everything and delivers *****

If it (they) has no internal faults and is competitively priced - get a few.

Maîneÿ . . .
AnswerID: 391589

Follow Up By: Member - Lia H (SA) - Wednesday, Nov 18, 2009 at 09:25

Wednesday, Nov 18, 2009 at 09:25
Hi.

It is a lot of six, for about $150. They are being sold off as they were part of a UPS system that is now not needed. They have *apparently* never been drained and always remained charge ready for use.

I guess for that price I'd have to take my chances....
0
FollowupID: 659484

Follow Up By: Maîneÿ . . .- Wednesday, Nov 18, 2009 at 09:30

Wednesday, Nov 18, 2009 at 09:30
Yes,
definately buy the lot

Maîneÿ . . .
0
FollowupID: 659485

Follow Up By: Member - Lia H (SA) - Wednesday, Nov 18, 2009 at 09:47

Wednesday, Nov 18, 2009 at 09:47
That's what I figured. I'm just new to the mystical world of power that doesn't come out of a house 240v plug. Thought I'd check...

:)
0
FollowupID: 659491

Follow Up By: Grizzle - Wednesday, Nov 18, 2009 at 16:27

Wednesday, Nov 18, 2009 at 16:27
Buy them! My mate worked for a company that did UPS' and me and a few of my mates have them. If one battery in the UPS system dies they replace them all. Sometimes the battery bank can have 10's of batteries in them.

Lifetime Member
My Profile  Send Message

0
FollowupID: 659547

Reply By: signman - Wednesday, Nov 18, 2009 at 09:38

Wednesday, Nov 18, 2009 at 09:38
I was given a 120ah deep cycle battery (ex RTA). I took it to my local Battery World and he checked it with his gizmos (for free!!), and gave it a clean bill of health. !!

AnswerID: 391596

Reply By:- Wednesday, Nov 18, 2009 at 11:16

Wednesday, Nov 18, 2009 at 11:16
G'day,

looking at the photo of yours with your lovely kids,
you've got enough to keep you busy...
But if you can dedicate some spare time to mucking around with a bunch of used batteries, yes go ahead an buy the lot.
Mucking around could mean:
finding space for them, ensuring the kids don't play with them, proper load testing of all six batteries in order to find the one which has the most residual capacity. Get this capacity measured, in order to be able to make up your mind if it's for you.
Once you've found out which one(s) are the best, you have to properly dispose of the others as they contain the controlled substance lead.
Try to have the battery of your choice wired up in your caravan, and do a 'test run' under real life/travel conditions, BEFORE you do the big trip.

Or, for only 50 bucks more you could get a brand new quality deep cycle AGM VRLA 12V/100Ah battery which will most likely outlast the lot you're currently looking at. Check them out on ebay.
Remember when taking your chances with used batteries, it doesn't just stop there when you find out they're not good enough. They need to be recycled properly, and then you can start fresh looking for new batteries.

Look out for AGM VRLA deep cycle batteries, as they're the battery of choice for caravan applications.

Good luck and best regards, mr.batteryvalue
AnswerID: 391605

Follow Up By: Maîneÿ . . .- Wednesday, Nov 18, 2009 at 11:39

Wednesday, Nov 18, 2009 at 11:39
I read it to be 6 x AGM Deep Cycle batteries and if they are actually tested as has been advised above, and they pass the tests, then I would have no problems in using them.

"It is a lot of six, for about $150.
They are being sold off as they were part of a UPS system that is now not needed.
They have apparently never been drained and always remained charge ready for use"

They are 100 ah AGM Deep Cycle batteries with a designed life span of 10 years, which have been used in UPS standby life so should be in as perfect condition as can ever be expected of any 12v battery.

All Lia has to do is take them to the battery tester, he will test them for her, no hassles usually, and then she will have 6 as new AGM DC's capable of a long life.

These are, as you have said "AGM VRLA Deep Cycle batteries"
so I would expect there to be no problems at all.

Maîneÿ . . .
0
FollowupID: 659514

Follow Up By:- Wednesday, Nov 18, 2009 at 12:32

Wednesday, Nov 18, 2009 at 12:32
Allright, here is a check list of things which everyone thinking of buying a secondhand battery should consider:

1) first installation date
2) type of load (standby, intermittent cycling, etc)
3) no ultra low discharges below cut-off voltage
3) average battery temperature during the whole period
4) charging voltage during the whole period
5) storage times at partially discharged condition

Can the checks above be proven by the seller, or do you just take his/her word for them?

Do you expect the 'battery tester' to be able/willing to do a load test way down to a low SOC, and then calculate the battery capacity from the result?
Only if this information can be obtained, I'd then be able to find out the residual life expectancy of the battery, by looking at the supplied float life graph (if I were convinced the battery actually was used in a standby application).

Best regards, mr.batteryvalue
0
FollowupID: 659516

Follow Up By: Maîneÿ . . .- Wednesday, Nov 18, 2009 at 16:11

Wednesday, Nov 18, 2009 at 16:11
mr.batteryvalue,
the 6 AGM batteries are only 3.5 years old, like my own AGM's they also have a "designed life span of 10 years" if Lia only gets another 4 years from them for just $150 they are still excellent value, but I will bet they last longer than the 10 years they are designed for.

Makes me wonder how long a normal battery will last used in the same way ??


Yes, I expect the 'battery tester' to be able and also willing to do a load test way down to a low SOC, it takes only 5 minutes.


mr.batteryvalue,
obviously you don't offer that service to your customers then ?

Maîneÿ . . .
0
FollowupID: 659545

Follow Up By:- Wednesday, Nov 18, 2009 at 16:48

Wednesday, Nov 18, 2009 at 16:48
Maîneÿ,

yep, good value, if they're really only 3.5 years old, and if they were treated, charged etc, the right way....too many ifs, you get my drift.

As to the battery load test:
I do them every day, but it takes longer than your specified 5 minutes.
Maybe, it's because I do a proper capacity test which I only achieve by loading the battery with a current of 55A over 30 mins and sample the terminal voltage in one minute steps. This way I can compare the discharge characteristics with the factory supplied graph, giving an excellent indication about the battery capacity.

I'm not quite sure how you can do a load/capacity test within 5 minutes.
Maybe your load tester takes high current pulse/impedance readings and then estimates the available capacity?
Would love to read your explanatory notes on this.

Best regards, mr.batteryvalue
0
FollowupID: 659554

Follow Up By: Maîneÿ . . .- Wednesday, Nov 18, 2009 at 16:54

Wednesday, Nov 18, 2009 at 16:54
To check the battery age they will have a date stamped on them, won't they.

How much do you charge to do the "proper" battery load test, you do daily ???

Maîneÿ . . .

0
FollowupID: 659556

Follow Up By:- Wednesday, Nov 18, 2009 at 19:37

Wednesday, Nov 18, 2009 at 19:37
Certainly, any date stamp gives an indication about the battery's age, but only if you manage to decipher it correctly...

Care to answer my question, as to how your battery tester might derive the
battery capacity from 5 minutes of testing?
Or did I get this wrong, and your battery tester only tests for maximum load
current capability and then goes to a pre-programmed lookup table and pulls
out the associated capacity, which is only an estimate of course?

When doing my daily load tests, I gain a thorough understanding about the
batteries ability to store the rated amount of Ah. In the process, I also get a
printout from the terminal voltage data logger set to one minute intervals, to
see how this voltage compares to the manufacturer specified discharge
characteristic @ the constant load test current. Note that this result is directly proportional to the battery capacity, provided the battery was at 100% full charge at the start of this 30 minute testing routine.

Just to satisfy your curiosity, no we don't charge for this load/capacity test.

Best regards, mr.batteryvalue

0
FollowupID: 659575

Follow Up By: Maîneÿ . . .- Wednesday, Nov 18, 2009 at 20:18

Wednesday, Nov 18, 2009 at 20:18
Your question: "how your battery tester might derive the battery capacity from 5 minutes of testing"
I'm unsure, I've never asked, they do their job and I do mine :-)

To be told the battery is efficient and holds it's charge is reasonable enough for most people.

Maîneÿ . . .
0
FollowupID: 659579

Reply By: Wilk0 - Wednesday, Nov 18, 2009 at 13:31

Wednesday, Nov 18, 2009 at 13:31
Hi Lia,


Doh I'll finish the before I hit update.

I was able to get 2 x 100a/h batteries which were due to a UPS upgrade they were 2 years old and I have had them for 3 years now.

I'd go for it $150 is cheap as.


Cheers Wlko


AnswerID: 391618

Sponsored Links

Popular Products (9)