I am getting ready to purchase my first battery to make a solar generator and was going to buy the Global Power 100ah on Ebay but the price went up. I noticed on Docan Power's website (Texas Warehouse) they have a 100ah battery with lowtemp cutoff and a smart bluetooth bms for $350. Has anyone purchased one of these? From other posts on here it seems Docan has a pretty good reputation for their cells but I haven't seen anything on their complete batteries. If anyone has some any feedback it would be helpful, thanks. Here is a link to it. Docan Power 12v 100ah Battery
Docan Power Battery
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AKvalleyguy
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If you want to series or parallel, you should check with them. Seem to remember they couldn't be connected but not certain.
Sback
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The only downside to there prebuilt is you can't series connect them. As long as your just looking for a 12v battery I don't think you can go wrong with it. I do no they use a 100 amp jbd bms with calb cells and they take quality control very serious. If I was looking for a 100ah 12v I would buy there prebuilt before building my own.
Which battery? In the video I see a 200A BMS, but the used cells only can provide 1C max current. So unless they derate the BMS, the video is not the actual product, or they use a different BMS than the video, something is wrong.
Also, the 200A BMS allows up to 2 packs in series, so a 24V setup should be possible.
Also, the 200A BMS allows up to 2 packs in series, so a 24V setup should be possible.
I don’t think there’s US stock.
Inquire with @Amy Zheng
Inquire with @Amy Zheng
Any idea if that 120ah Global Power battery actually has low-temp charging cutoff?
I asked Global Power in an Ebay Message, and he said it did. I am not going to tear the battery apart to test it. When I take it camping I will have it in the front pass through storage area of the camper to keep it warm. I don't think you can go wrong with either the Global Power 120ah for a lower price or the Docan Battery. The Docan would be really nice with the Bluetooth BMS. I just didn't have quite enough at the time for it so I went with the slightly cheaper battery.
The Docan Bluetooth BMS is a great feature, but sad to hear they don't support using the battery in parallel as I was planning for a pair of them.
@Amy Zheng can you help here?
Hi Amy! I'm new to this. I am just looking to connect 2 12v 100Ah batteries together in parallel to increase the run time. Why does the internal BMS affect that?
Thanks!
meetyg
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I was thinking about this: Why wouldn't the BMS support a parallel connection?
Just a guess: If using two 100Ah batteries in parallel, with a 100A BMS, when all is good they will share the load (200A max load).
But, when one BMS cuts out because of low voltage, the other BMS will have to handle all the 200A loads. That's twice the rated amperage of these 100A BMSs.
I would suspect that in order to properly do parallel, they would need to put a higher rated BMS to handle these cases.
As reality shows, two identical batteries in parallel almost always will charge/discharge at a bit different rate. At least just enough to get one of them to cut out earlier than the other.
In my non-expert opinion, if you need to parallel just for Ah capacity and not for doubling the load capacity, you should be able to do parallel. For example, if you make sure your loads never exceed 80% of a single BMS's rating , then you can connect the batteries in parallel. You will get twice the running time. When one battery cuts out, the other will handle a load that is still under its maxium rated amperage.
In short if you have only 80Ah loads in total, it should be possible to parallel.
Just a guess: If using two 100Ah batteries in parallel, with a 100A BMS, when all is good they will share the load (200A max load).
But, when one BMS cuts out because of low voltage, the other BMS will have to handle all the 200A loads. That's twice the rated amperage of these 100A BMSs.
I would suspect that in order to properly do parallel, they would need to put a higher rated BMS to handle these cases.
As reality shows, two identical batteries in parallel almost always will charge/discharge at a bit different rate. At least just enough to get one of them to cut out earlier than the other.
In my non-expert opinion, if you need to parallel just for Ah capacity and not for doubling the load capacity, you should be able to do parallel. For example, if you make sure your loads never exceed 80% of a single BMS's rating , then you can connect the batteries in parallel. You will get twice the running time. When one battery cuts out, the other will handle a load that is still under its maxium rated amperage.
In short if you have only 80Ah loads in total, it should be possible to parallel.
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Sback
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I just ordered one of docans 12v prebuilt batteries. I looked at the part number for the bms and it was the 100ah jbd that CAN be series connected or paralleled. This was just in the one I bought, hopefully they continue to use that bms. This is something we will never no unless they put the part number on the battery label or correct there specifications on the label. When parallel a battery you should never exceed the capability of 1 bms.
There are several threads discussing this, try a google search with this text: battery compression site:diysolarforum.com
Lots of results.
The bus bar hole distance should accommodate your cells side by side. If that's not the case perhaps you got the wrong ones.
It's not so much to 'compress' them as it is to hold them snugly and prevent puffing. They really shouldn't puff, but some do at full charge. And it's not so much that that is damaging in and of itself, but it can cause your bus bars to pull the terminals and that's not good, and CAN be damaging.
Some cell manufacturers have a higher number of rated cycles for their cells when placed in a compression jig. There are lots of images and diagrams of these in the threads here.
Here's how I did mine:
Wait...what? I believe you better invest in a lot more research keepsake. Shoot for a commonly accepted voltage for your system and then decide upon the appropriate BMS to match your needs. ALSO...test those 17 batteries before doing anything...this alone will add to your battery wisdom coefficient. Have funand be sure to wear wear goggles/face shield and gloves..
Wait...what? I believe you better invest in a lot more research keepsake. Shoot for a commonly accepted voltage for your system and then decide upon the appropriate BMS to match your needs. ALSO...test those 17 batteries before doing anything...this to insure you have received the quality of cells (grade A?) that you paid for. ALSO...be sure to have fun and wear goggles/face shield and gloves. These puppies a relatively safe yet can pack a huge punch. There is a reason Will Prowse is often in full protective gear.
