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Gel Battery testing in Pretoria

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Good day all, i would like to find out if there is someone in Pretoria that can test a gel battery and provide me with some sort of report on it? 

Got a 200ah gel battery with inverter from MacSellSolar https://macsell.store/products/gel-battery-200ah-12v?_pos=1&_sid=d05e6c189&_ss=r

The problem with it is on a 300W load it goes down to 12.2V in a space of 20min, that does not seem right to me, thats like 40% in 20min gone, i took it back and they argued that it sounds fine to them and didnt even bother to test, i doubt they have a tester even.

so now i would rather like a professional report of the battery to give to them and prove to them that their battery they sold me is borked.

Battery in question is a Sun God DG12-200

12 minutes ago, Voldoverse said:

Good day all, i would like to find out if there is someone in Pretoria that can test a gel battery and provide me with some sort of report on it? 

Got a 200ah gel battery with inverter from MacSellSolar https://macsell.store/products/gel-battery-200ah-12v?_pos=1&_sid=d05e6c189&_ss=r

The problem with it is on a 300W load it goes down to 12.2V in a space of 20min, that does not seem right to me, thats like 40% in 20min gone, i took it back and they argued that it sounds fine to them and didnt even bother to test, i doubt they have a tester even.

so now i would rather like a professional report of the battery to give to them and prove to them that their battery they sold me is borked.

Battery in question is a Sun God DG12-200

For starters you will need to ensure it is fully charged. This can take an easy 24hrs depending on charge current and SOC. 

Based on 300W load the current is about 24A. To power said load to 50% SOC means 4 hrs. You have reason to be unhappy. 

Once charged you can take it to a battery shop and ask them to do a load test at 24A. Time consuming. The battery testers might give a result in seconds. 

  • Author
19 minutes ago, Scorp007 said:

For starters you will need to ensure it is fully charged. This can take an easy 24hrs depending on charge current and SOC. 

Based on 300W load the current is about 24A. To power said load to 50% SOC means 4 hrs. You have reason to be unhappy. 

Once charged you can take it to a battery shop and ask them to do a load test at 24A. Time consuming. The battery testers might give a result in seconds. 

Thanks, yes battery was charged at 15A for 22hrs, pretty sure it must be full by then? I see you are from PTA, do you have any recommendations about where i can get it tested?

7 minutes ago, Voldoverse said:

Thanks, yes battery was charged at 15A for 22hrs, pretty sure it must be full by then? I see you are from PTA, do you have any recommendations about where i can get it tested?

Cannot say your battery was fully charged as the charge current could have been 15A but over time the current would drop quite a lot as it reaches fully charged state. 

Years ago I took a car battery to the Bosch workshop in Centurion and they gave me a printout that the battery is defective. This was my proof to a battery dealer who would not accept that the new battery they sold is defective after only 2 months. I then Gog a replacement. This says a lot about the 12/24 month warranty one gets. 

Edited by Scorp007

  • Author
12 minutes ago, Scorp007 said:

Cannot say your battery was fully charged as the charge current could have been 15A but over time the current would drop quite a lot as it reaches fully charged state. 

Years ago I took a car battery to the Bosch workshop in Centurion and they gave me a printout that the battery is defective. This was my proof to a battery dealer who would not accept that the new battery they sold is defective after only 2 months. I then Gog a replacement. This says a lot about the 12/24 month warranty one gets. 

Ok, perhaps a place that tests batteries can then charge it fully and then test it for me, or else ill be sure to charge it also for 24hrs myself, any suggestions for a place that can test it for me?

8 minutes ago, Voldoverse said:

Ok, perhaps a place that tests batteries can then charge it fully and then test it for me, or else ill be sure to charge it also for 24hrs myself, any suggestions for a place that can test it for me?

Any battery dealer should have chargers that can charge the battery. Just phone and ask various battery dealers. Here I don't mean just a seller. 

Sorry to highjack your conversation @Voldoverse @Scorp007 just wanted to give 1 input about the conversation above just in case the supplier wants to get technical. I have worked with quite a few of these gel,agm and wet lead acid deep cycle batteries. They are mostly C/20 batteries or 0.05C meaning you need to discharge them in 20 hours. 200/20=10 amps in 20hours. Should you exceed the 10 amps discharge current you loose capacity with 24 amps discharge current it is more than double the allowed discharge current. Gel Agm and Sla suffers the Peukert's affect. Gel performs well in large battery banks.

  • Author
23 minutes ago, TaliaB said:

Sorry to highjack your conversation @Voldoverse @Scorp007 just wanted to give 1 input about the conversation above just in case the supplier wants to get technical. I have worked with quite a few of these gel,agm and wet lead acid deep cycle batteries. They are mostly C/20 batteries or 0.05C meaning you need to discharge them in 20 hours. 200/20=10 amps in 20hours. Should you exceed the 10 amps discharge current you loose capacity with 24 amps discharge current it is more than double the allowed discharge current. Gel Agm and Sla suffers the Peukert's affect. Gel performs well in large battery banks.

i see, so you are saying my results are expected?

4 minutes ago, Voldoverse said:

i see, so you are saying my results are expected?

No not at all. It's the devil in the detail. Discharging @24A instead of the spec 10A would reduce the output to say 150-180Ah instead of 200Ah. This is normally contained in the specs. 

  • Author
14 minutes ago, Scorp007 said:

He indicated 2 months. 

16 minutes ago, TaliaB said:

Just one question how long have you been using this battery?

Been Using it since Saturday the 29th of July, purchased new, so 2 days actually haha

15 minutes ago, Scorp007 said:

No not at all. It's the devil in the detail. Discharging @24A instead of the spec 10A would reduce the output to say 150-180Ah instead of 200Ah. This is normally contained in the specs. 

Ah i see so a little bit of available capacity is lost but nothing as extreme as i have, understood.

 

Edited by Voldoverse

2 minutes ago, Voldoverse said:

Been Using it since Saturday the 29th of July, purchased new, so 2 days actually haha

Ah i see so a little bit of available capacity is lost but nothing as extreme as i have, understood.

 

I just don't think these gel batteries have the energy density to cope with the load shedding schedules. If you look at the flip side of the coin you also need 10 hours minimum to charge the battery to 90% soc replacing the bulk then you still need the absorption cycle time ,you don't have this between LS stages. With this scenario your battery will never be fully charged. Gel batteries generally require a specific charge profile.

27 minutes ago, Scorp007 said:

He indicated 2 months

Sorry yes missed that part.

  • Author
3 minutes ago, TaliaB said:

I just don't think these gel batteries have the energy density to cope with the load shedding schedules. If you look at the flip side of the coin you also need 10 hours minimum to charge the battery to 90% soc replacing the bulk then you still need the absorption cycle time ,you don't have this between LS stages. With this scenario your battery will never be fully charged. Gel batteries generally require a specific charge profile.

Sorry yes missed that part.

i thought perhaps it didnt charge enough, we got lucky on sunday and i managed to charge it for 22 hours and thought that should be enough but the result ended the same

6 minutes ago, TaliaB said:

I just don't think these gel batteries have the energy density to cope with the load shedding schedules. If you look at the flip side of the coin you also need 10 hours minimum to charge the battery to 90% soc replacing the bulk then you still need the absorption cycle time ,you don't have this between LS stages. With this scenario your battery will never be fully charged. Gel batteries generally require a specific charge profile.

Sorry yes missed that part.

You are spot on but having a 15A charger after 22hrs you should be at abou 90% SOC and the last 10% can take ages. 

All that one can say is that the battery should last quite a few hrs even from 90% and not less than 30min.

3 minutes ago, Voldoverse said:

i thought perhaps it didnt charge enough, we got lucky on sunday and i managed to charge it for 22 hours and thought that should be enough but the result ended the same

Look it is very possible you have a factory defective battery so get it checked out by a battery specialist and take it from there.

 

1 minute ago, Scorp007 said:

All that one can say is that the battery should last quite a few hrs even from 90% and not less than 30min

Yes i agree factory dudd worth to get it checked out.

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