#148878  by The Moersches
 Mon Feb 11, 2019 8:47 am
Hi,

Should we buying an AGM or Gel battery to run solar?
I was thinking that 150-200Ah would be best, but budget is only around $500-$550.
Where is the best place in Auckland to buy batteries?

More info:
We have a 1979 Lightweight Expander poptop caravan (with hard sides). We are looking to get out of Auckland every 3-4 weeks for 3 days at a time. So not huge use really.

I have already bought 140w monocrystalline folding solar panels to run (or partially run) a little 42W fridge. We have a standard 240V plug in our Landcruiser so if we need to run it via that for a couple of hours, or even switch the fridge off overnight, that is fine. We don't need to run heaters, devices, lights (we have little battery powered fairy lights which are fine) so we didn't go with the huge panels, and we got folding because its a popup, so thought portable would be best.
 #148882  by Skiwi
 Mon Feb 11, 2019 10:25 am
https://www.batterystuff.com/kb/article ... s-agm.html

https://northeastbattery.com/agm-vs-gel-technology/

I chose AGM mainly because they supposedly handle "burst" draws better (like when I use the microwave)

Cheers
Skiwi
 #148885  by NeilV
 Mon Feb 11, 2019 1:43 pm
I recommend AASolar, who will also help you design and install your system if needed too.

I went AGM for price and versatility reasons.
 #148886  by The Moersches
 Mon Feb 11, 2019 2:27 pm
Sounds like AGM is the way to go.
AAsolar look like they have some pretty unfavourable reviews. Any other options on AGM battery supplies in Auckland?
 #148892  by petercw
 Mon Feb 11, 2019 8:24 pm
Firstly aasolar are in New Management in recent times and they know what they are doing.. Second I purchased from the previous owners and they were nothing but helpful, so much so that I bought a complete solor\battery diy kit and installed it myself..I went with AGM for price and and am not disappointed..I have 160w solar, 2 x 100agm amphrs, and I run a12v fridge, tv, pumps, etc.. Of you are in the South then you need more solar.. About 300w. Min. :TU
My system is about 3 years now and going fine.
 #148895  by vansvilla
 Tue Feb 12, 2019 1:41 am
For batteries, try Energyunlimited.
A company in Auckland that specialise in LED, solar and batteries.
They were selling a hybrid battery that out performed AGM or Gel.
 #148908  by GaryB88
 Tue Feb 12, 2019 7:12 am
I would also now recommend AASolar, which is under new management and now very customer focused. Their AGM battery prices are hard to beat. Give them a visit to discuss what you want to do, and make your own call on the service you get.
 #148918  by Neddy
 Tue Feb 12, 2019 12:37 pm
Those hybrid AGM/GEL batteries are quite cheap. While their performance will not be as good as batteries costing a lot more, measured on a “cost per cycle” basis they could nevertheless provide quite good value. I have got 10 years use out of a set of “bottom of the market” AGM batteries, for example.

One of the best ways of assessing the quality of an RV battery is to look at its “Life Cycles vs Depth of Discharge” plot. Unfortunately, SunnyTech (along with a few other suppliers) are unwilling or unable to provide this information. All SunnyTech will say is that at 50% battery drawdown, their batteries have a life of 800 cycles.

To get this into perspective, here is what you can expect from a good quality (ie expensive) Deep Cycle AGM battery.
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Here is what you can expect from a good quality Deep Cycle AGM/Gel Hybrid battery.
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Here is what you can expect from a cheap Deep Cycle AGM battery
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Many batteries advertised as being "Deep Cycle"..... aren't. According to Wikipedia "A deep-cycle battery is designed to discharge between 45% and 75% of its capacity, depending on the manufacturer and the construction." Typically, "Deep Cycle" batteries that are not really “deep cycle” at all will come with specifications that look something like this :-

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Neville.
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