Charging a Renogy Hybrid GEL with 30a/12v power supply

[geekdw]

Hi, I am new to the forum, and I'm also pretty new to solar and electricity in general, so go easy on me! A lot of this stuff is new to me and still confusing. So here's my question...

I'm building a Renogy solar charging station. 100w panel, 30a charge controller, 100ah Hybrid GEL battery, and 1000w inverter, all from Renogy. I think I've pretty much got all that in order, but I was wondering if I could use a 30a/12v power supply to charge the Hybrid GEL battery?

I've got the power supply, but I don't want to try charging the battery with it before I check with the community to make sure it will be okay to do that. If so, can I just clamp some 10awg wire to the battery from the power supply? Or do I need something in between them? I've seen Will put a fuse box in between power supplies and batteries, but it hasn't been to a GEL battery, and my particular power supply is 30a (that's the max charge current of the battery), and the power supply has over-voltage and over-current protection, and "surge protected outputs". So I'm assuming I can just run the power supply DC connection to the battery directly, but again I am new to this stuff.

Edit: Or should I run the cable from the power supply into the charge controller in the same ports that the solar panels go in?

 

[snoobler]

Welcome to the forum.

If you direct connect to the battery, you'll need to set it to the battery's float voltage (13.8V), and you'll only get a max of 138W of power for charging.

If you connect to the SCC PV input @ 30V/10A, you can charge at 300W.

 

[geekdw]

Thank you for the quick answer! So it sounds like it will be ok to direct connect the power supply to the battery, I was just scared to do that. Would I need to get a different power supply to be able to do the 2nd option you mentioned at 300W? The power supply I have is 30A and 12V, and output voltage is adjustable 15%.

 

[snoobler]

I was thinking the typical 30V/10A supply even though you clearly indicated 30A/12V in the subject.

SCC option is off the table. SCC input voltage needs to be higher than battery voltage.

You can only connect it directly to the battery at 13.6-13.8V. If you can't adjust to that level, it's no good. Not also that it will take a long time to fully charge at that voltage. That's a standby voltage, so it takes quite awhile to get fully charged - probably something like 24 hours if I had to guess. You'll get a fairly quick initial charge, but it will take many hours to top it off.

You would probably be better served by an actual charger of some kind.

 

[geekdw]

Thank you so much!

 

[geekdw]

I have my power supply set between13.6 and 13.8V connected directly to the battery. Can I leave it there indefinitely to ensure it stays topped off? Or should I be disconnecting it because it's not a regulated charger?

 

[snoobler]

As long as the float voltage of the battery is in that range, that's fine.

 

[Substrate]

I'm going to add a little of my own advice, having worked with MK's and Deka gels for mostly standby solar..

It may seem like a pithy change from snoobler's excellent advice, but in the case of gel's they like to be pampered just a little bit compared to fla or agm. Even in float voltage.

My suggestion is to float at no more than 13.5v. As measured at the battery terminals.

The Renogy hybrids, just like the Might Max gel hybrids, are constructed like an agm, (lower IR than before) but at their heart with gelled (thixotropic) electrolyte, still obey the same gel rules.

Many consumers get hoodwinked into thinking it's ok to treat a gel like an agm, and basically throw much of their extended cyclic life advantage away.

If you do go solar with it, set your CV to no more than 14.1v. Preferably temperature compensated at the battery terminal probe.

You'll read a lot of conflicting information about gels, which turn out to be mostly 30 year-old marketing attempts to push them into the agm marketspace and make them seem equal in operational voltages for consumer's convenience. Reduced life is the result of that.

 

[Substrate]

Here is an excellent recent 2020 example of marketing still pushing gels into agm marketspace, and suffering as a result.

They compare the older classic-style of Gel, to the new Hybrid style with agm-construction, and expect an agm in gel clothing!

Renogy 12V 100Ah Deep Cycle AGM, Gel and Lithium Batteries

Renogy 12V 100Ah Deep Cycle AGM, Gel and Lithium Batteries

www.deepcyclemarinebattery.com

Lo and behold, less IR due to the agm-type construction, BUT the push is on to increase the CV voltages into that agm range, and they are puzzled about apparent loss of cycles with the hybrid.

The use of lower IR to make it seem like Gel's can be treated like AGM's, is a basic misunderstanding of how that electrolyte works.

If they wanted to get the most from EITHER type, then treat it like an East-Penn / Deka gel with a nominal 14.10v cv, and test again!!

I'm also dubious of the 0.3C charge capability too. Lower IR means faster recharge, but Gel's being what they are, kindness and respect will get you farther with them. For the hybrid, I'd automatically cut that back to no more than 0.20C. (I still need to long-term test this, but will need a few more lifetimes to do personally.)

 

[Substrate]

That's part of the problem - one has to actually verify what a manufacturer thinks "voltage protection" is and either is ignorant of what a gel truly needs, or is pushing a marketing agenda.

Ie, it's up to the consumer to verify that the CV is only 14.1v and not some gel/agm combo button. With an SCC, one has to carefully check the "sealed" setting too to verify that it is truly the CV voltage they want.

So many consumer chargers and too little time. But if one cares about this, they will.

A manual that has served me well comes from East-Penn/Deka. Specifically page 11, and then page 4 showing what happens when you deviate into agm voltage land..

http://www.eastpenn-deka.com/assets/base/0139.pdf