diy solar

diy solar

Renology 200Amp Gel on sale at Amazon

D

Donald Siegel

New Member
Joined
Sep 24, 2019
Messages
78

Attachments

  • Renology.PNG
    Renology.PNG
    770.7 KB · Views: 9
If you keep an eye on these on Amazon, you'll see the price go up and down A LOT. $350 shipped is a great deal though. I paid $400 a year ago. I have 2 and they have been workhorses!!
 
I use them for a year and they are no longer good. I recommend not to use gel batteries at all, Instead build your own lithium.
 
alexmartin said:
I use them for a year and they are no longer good. I recommend not to use gel batteries at all, Instead build your own lithium.
Click to expand...
If by lithium you mean 18650 power walls, they have their own issues, micro shorts, balance issues and fire hazard being just some. If you mean LifePO4 those are great but still way more than $350 for a 200 amp 12v battery, more like $800. If you draw from the battery daily the LifePO4 are the better deal as they last so long. If you want a power backup, or a part time off grid use, gel may still be the better deal as it will take years to cycle them out at a 50% discharge.
 
Last edited:
Donald Siegel said:
If by lithium you mean 18650 power walls, they have there own issues, micro shorts, balance issues and fire hazard being just some. If you mean LiPO4 those are great but still way more than $350 for a 200 amp 12v battery, more like $800. If you draw from the battery daily the LiPO4s are the better deal as they last so long. If you want a power backup, or a part time off grid use, gel may still be the better deal as it will take years to cycle them out at a 50% discharge.
Click to expand...

Or if your batteries are going to get cold.
 
alexmartin said:
I use them for a year and they are no longer good. I recommend not to use gel batteries at all, Instead build your own lithium.
Click to expand...

What depth of discharge did you take them to? A year is pretty short.
 
You just said they were no longer good and not worth using. Not a great salesman tactic :LOL:
 
my standards are high. And i am building 400 AH battery myself.
I am getting shipment tomorrow to build the beast
 
I tested my second 200amp Renology Gel as I have the shunt now and wanted to insure they were both performing as expected. I got 2000 Wh taking it down to about 50%. With both batteries I have 4kWh of energy storage for $700. While they won’t last as long as LiFePO4s and they are massive your not going to get close to that kind of storage with LiFePO4s at 3x the price.
 

Attachments

  • C1FCDECC-E81B-4AB2-8DC3-927F7F699299.jpeg
    C1FCDECC-E81B-4AB2-8DC3-927F7F699299.jpeg
    109 KB · Views: 6
2 of those batteries are my max $$$ for my off grid hunting cabin. What setup are you using to power them? And what are you able to pull from them? I was considering going all renogy and do 4-6 of the 100w panel kit they offer.
 
Chris G said:
2 of those batteries are my max $$$ for my off grid hunting cabin. What setup are you using to power them? And what are you able to pull from them? I was considering going all renogy and do 4-6 of the 100w panel kit they offer.
Click to expand...
I have four 250 watt used San Tan Solar panels mounted on a side yard wall ($50 each). I get 100-400 watts of solar power depending on the season and time of day. I use a 24v MPP Solar all in one. It’s set up as an off grid power supply to one room in our home that draws 125 watts or so to run led desk lights, a PC, Echo Dot and phone charger. While this setup will actually provide continuous one room emergency power in a blackout and it runs my man cave off grid every day, it has really just been a hobby. I did not want to do solar roof panels, so got involved in a smaller way.
 
Donald Siegel said:
I tested my second 200amp Renology Gel as I have the shunt now and wanted to insure they were both performing as expected. I got 2000 Wh taking it down to about 50%.
Click to expand...
Donald Siegel said:
75% discharge it hit 2300Wh
Click to expand...

You are killing your battery with those tests. If you pull 2300wh out of a 2400wh battery, you did not only take it down 75%, you took it past 95%! These aren't lithiums, you can't test them like this!
 
Yes, the depth of discharge vs number of cycles is a downward curve and you want to stay to the left side. But it’s not a steep slope past 50% and a single test of a battery to 70% DOD likely did not kill my battery. What’s interesting is how you decided the depth I reached. I went with voltage as a cut off 11.74v = 70% not 95+% DOD in the first test,11.94v = 55% not 83% in the second. You did the math on labeled volts and amps to get Wh (2400) and what I drew out, (2200Wh) and come up with a >95% DOD, very different than 70% the voltage tables show. In the second test I went to relatively safe 55% DOD but you would say 83% by the same math. So do we toss voltage state of charge tables and quit using voltage as an endpoint to determine DOD?
 

Attachments

  • 48D7DA50-9680-4FFC-8C72-9F1C2C54E41E.jpeg
    48D7DA50-9680-4FFC-8C72-9F1C2C54E41E.jpeg
    54.2 KB · Views: 6
  • 3E47502F-D9C0-415E-89E5-5CA68E80B281.jpeg
    3E47502F-D9C0-415E-89E5-5CA68E80B281.jpeg
    79.5 KB · Views: 5
Voltage is not an accurate way to determine SOC, it's a ballpark guideline only. A brand new battery at 50% will have a higher voltage than a 1 year old battery at 50% in my experience. An ammeter is the only accurate way I know of to determine when I reached my desired DOD. You have to trust what the ammeter is telling you with LAs. Gel cells are much less forgiving than FLA, so treat them good.
 
Renogy has done extensive testing on these batteries, and they are one of a handful of reputable battery suppliers. I would trust their research and not worry about testing them, because you certainly aren't doing them any favors, as SolarRat has pointed out. From Renogy's website:

Screenshot_20191210-074520_Chrome.jpg
 
There is always more to the story. They were providing little power before my transfer switch in my MPP would low voltage cut off and move to utility power. I had the cut off at 12v under a light 150 watt load which was about 12.4v with the load off. I was concerned I got a bad battery and pulled them out of series to make them stand alone 12v batteries. I charged them slowly at 10 amps to get a good charge. I then connected them to a 12v stand alone inverter drawing 140-150 watts to see if one or the other needed to be returned. I was happy they both are functioning normally and am back to a lower DOD. I need to figure out new settings on my PIP to get a decent but safe discharge before I cut to utility. Regarding how to decide DOD I’m hearing no load resting voltage and tables is not accurate in determining where you are on DOD? If that is so exactly what is a valid alternative DOD measure? A link to a vid explaining this new method would help.
 
Donald Siegel said:
Regarding how to decide DOD I’m hearing no load resting voltage and tables is not accurate in determining where you are on DOD? If that is so exactly what is a valid alternative DOD measure? A link to a vid explaining this new method would help.
Click to expand...

For me, using my batts for the boat motor, I just reset my amp/hr meter before the trip and try and get home before 50%. That method also works on an emergency backup system, but it's obviously that's not a solution for most daily cycle applications.

For daily cycle use without user intervention I'd set your cut-off to a reasonable voltage. Depending on load that could be 11.8 for a higher load or 12.1 for a small load...you'd have to experiment. What is important is that you size your bank adequately enough that you'll rarely hit that limit. If you hit that limit every night you need more batteries!
 
New Mexico Will said:
What depth of discharge did you take them to? A year is pretty short.
Click to expand...
about 65%.
The good news is that Renogy replaced with new battery. So if any one need brand new renogy 200 AH GELL battery sent from the company for free,i can give you $100 off. Just let me know.
 
You must log in or register to reply here.

Similar threads

rezonatefreq
Guidance on System Voltage and Current Flows Truck Camper with LifePo4, Solar, Alternator, Convertor.
Replies
6
Views
507
sunshine_eggo
sunshine_eggo
Laughingman
Buying the second cheapest solar generator on amazon. Testing and review.
Replies
0
Views
1K
Laughingman
Laughingman
Maast
Easy simple DIY LFP battery tester build instructions, supply list, and diagram
2
Replies
27
Views
4K
Oldtgeezer
O
Back
Top