Changing batteries with solar question

[Bill and Earline]

And Leon, I'll really be impressed if you made the change to the charging profile described in post number 18--the switch to AGM.

[John in Santa Cruz]

Originally Posted by RangerMan

I see they meet mil-spec requirements. That is expensive!

there are millions of mil-specs, some are pretty silly.

[John in Santa Cruz]

Originally Posted by gbaglo

I'm thinking I will stick with my Trojab 27 TMX.

excellent choice for a group 27.

[RangerMan]

Originally Posted by John in Santa Cruz

there are millions of mil-specs, some are pretty silly.

Silly and still expensive!

[oldwave]

Originally Posted by Vermilye

Three Battleborn GC2's. The original installation description is here. I added the third battery this spring.

Nice and well documented. I also was in audio tech among others (it pro)
In the late 90’s I was a contractor for the Rock Hall as a recording engineer, multi tracking concerts. Plus lots of audio system designs. I recorded about 60 shows there. Some big fun and up to 48 tracks.

[John in Santa Cruz]

Originally Posted by Vermilye

Three Battleborn GC2's. The original installation description is here. I added the third battery this spring.

a GC2 is a 6V battery... not sure how you'd use three 6V batts in a 12V system.

the usual Battleborn 100AH batt is approximately Group 31 size, albeit with different terminals than a BCI Group 31.

[LarryandLiz]

Originally Posted by LarryandLiz

? is AGM for Solar "a thing" so if you focus on running via SOLAR you need a AGM for Solar ...

Reason I ask GoPower recommends 6 Volt Sun Cycle AGM Solar Battery GP-AGM-224-6V

https://gpelectric.com/products/6-vo...solar-battery/

the interstate battery doesn't say 'for solar'
https://www.interstatebatteries.com/products/gc2-hd-agm

Cash grab or a real thing

By the way ... thanks for all the info about covering up mounted solar panels when unhooked from batteries. much appreciated

Larry

I'm trying to decide between AGM or the 'regular' flooded deep cycle batteries

my application: at the end of this season, I'm planning on getting a COMPRESSOR fridge to replace my much-discussed dometic fridge (rm8551) trade it out for a NOVA KOOL R3800 which has a draw of 2.4amp hours with a battery cut-in rate of 11.7 and cut-out rate of 10.4 I'll be running with 160W roof mounted and 130W portable gopower solar panels

GOPOWER Suncycle For Solar AGM - says their AGM batteries will give the following:
00% Depth of Discharge ~ 250 cycles
50% Depth of Discharge ~ 1100 cycles
30% Depth of Discharge ~ 2250 cycles

MY QUESTION: the GOPOWER Suncycle AGM seems like the correct choice since it is recommended by the solar manufacturer of my panels. Perhaps it doesn't really matter which AGM I go with. But perhaps Flooded would be ok if my camping ambient temperature up here in BC doesn't often run the batteries too far down ? I'm musing here and interested in opinions - leaning towards the AGM since they seem to handle depth discharge at least as per GOPOWER information.

here is GOPOWER info re their AGM battery
https://gpelectric.com/products/6-vo...solar-battery/

Larry

[John in Santa Cruz]

all AGM's have decent deep cycle (where 'deep' is no more than 50%) characteristics.

[Centex]

Originally Posted by John in Santa Cruz

a GC2 is a 6V battery... not sure how you'd use three 6V batts in a 12V system.

the usual Battleborn 100AH batt is approximately Group 31 size, albeit with different terminals than a BCI Group 31.

FYI, in Battleborn terminology the 'GC2' model is a 12volt nominal unit, matching the physical dimensions of a BCI GC2 battery case:
https://battlebornbatteries.com/prod...cycle-battery/

So, three 'Battleborn GC2' work just swell in a 12V nominal system

[Vermilye]

Originally Posted by John in Santa Cruz

a GC2 is a 6V battery... not sure how you'd use three 6V batts in a 12V system.

the usual Battleborn 100AH batt is approximately Group 31 size, albeit with different terminals than a BCI Group 31.

Battleborn also makes a GC2 size/format 100 amp hour 12V battery. They charge an extra $100.00 for it (although if you talk nice on the phone, they will deal).

I originally used them so 2 would fit in the existing Escape battery box. When I went to 3 batteries, I built my own tie downs for the batteries. 3 Group 31 would not have fit under my rear bench - I have the hardware for the Lagun table mount taking up the central part. 3 GC2 format batteries just fit.

[oldwave]

Originally Posted by Vermilye

Battleborn also makes a GC2 size/format 100 amp hour 12V battery. They charge an extra $100.00 for it (although if you talk nice on the phone, they will deal).

I originally used them so 2 would fit in the existing Escape battery box. When I went to 3 batteries, I built my own tie downs for the batteries. 3 Group 31 would not have fit under my rear bench - I have the hardware for the Lagun table mount taking up the central part. 3 GC2 format batteries just fit.

Nice install, Lithium is on the agenda for next years mods as well as the second panel.

[LeonW]

Originally Posted by Bill and Earline

And Leon, I'll really be impressed if you made the change to the charging profile described in post number 18--the switch to AGM.

Bill, I changed the profile. That was the one bit I found online somewhere. As to the upper body strength, well that was a one time operation (I hope). 🙂

[Brian B-P]

Originally Posted by John in Santa Cruz

a GC2 is a 6V battery... not sure how you'd use three 6V batts in a 12V system.

the usual Battleborn 100AH batt is approximately Group 31 size, albeit with different terminals than a BCI Group 31.

GC2 is a size, usually used only for 6 volt batteries. Battleborn sells "12 volt" (4-cells-in-series LiFePO4) batteries in the GC2 size, presumably for RV owners who have battery compartments and trays sized for GC2 batteries; however, they offer only 12-volt replacements and one 24-volt (not 12 volt and 6 volt to suit the actual requirements). 2-cells-in-series (6 volt) modules with a BMS designed for a set of series-connected modules would be a technically superior solution, but apparently for a thousand bucks you don't get that level of sophistication.

For people who want about 300 Ah capacity at 12 volts in LiFePO4, Battleborn offers this as one unit in both 8D size (21.29 × 11.59 × 10.01 in) and what they call "GC3" (22.83 × 7.09 × 13.15 in). Either of these large sizes or any three of the 100-amp sizes total about the same weight and volume. One 8D has almost the same dimensions as three GC2 in a row (long sides adjacent). They're also about the same price, even though the single large units should cost them less to build due to a simpler BMS (one higher-current 4-cell BMS instead of three lower-current 4-cell BMSs). Of course the whole 40 kg (80 pound) mass must be lifted as one unit during installation. I think the larger units are only relatively recently available.

[Dee Lirious]

a word of waning if not already mentioned some where
capacitors STORE ENERGY
simply turning it of, isolating or disconnecting anything will NOT dissipate the stored charge in the capacitor
Now whether this stored energy is enough to do personal injury or damage equipment is beyond my pay grade, but I do KNOW that they store a charge and it can be substantial.
Many of us old timers who remember the days of points and plugs maintenance likely recollect discovering this the hard way

[MBA80]

Make sure you cover the panels when swapping the batteries. Also change your battery type profile on the charge controller if appropriate (ie. changing battery type wet vs AGM or lithium for example). Do not run with the wrong battery profile. Also decide if you are running the batteries in parallel or series for 12 volts.

[lostskier]

Sometimes....I really shouldn't read these blogs, LOL. I replaced my stock batteries with Renogy 6volt, AGM's last year. I just unhooked the old ones, hooked up the new ones, and reprogramed the charge controller to AGM batteries. Had just the normal amount of sparks when attaching the new battery terminals, LOL. Everything still works so must have done it right.

[Beekeeper]

Originally Posted by RangerMan

One could simply have the new battery(s) ready and wait until it gets dark.

Brilliant!

[Schmell]

Originally Posted by Donna D.

I'm in the same boat, I'll be replacing mine too. But with the same as currently in the trailer. I'd really appreciate a step-by-step list in how to safely remove the batteries (with the stock solar panel and controller), to how to reinstall! Like written for a third grader

I'm looking for this step-by-step list, Donna did you ever get one? I'm replacing my stock interstates with Trojan T105's and would love some advice. I know I have to cover the panels, but I'm not skilled enough to be adding switches and things like that.

[John in Santa Cruz]

for dealing with GC-2/T105 golf cart batteries it really helps to have a golf cart battery strap, thi sis a handle that clips onto those two square lugs on the top of the batt. you can see this strap/handle sitting on top of the old battery box here...





I swapped my GC batts without disconnecting or covering my old 160W stock solar panel with the GoPower PWM controller as at the time I wasn't aware that was recommended practice. When I installed my much larger 360W solar panel with a MPPT controller, I added a solar cutoff switch near the controller to make maintenance easier.

I always disconnect the negative terminal first, then the bridging cable, then the positive cable, then lift each batt out, place the new ones in, and reconnect in the opposite order (+ first, then the bridge cable, then the -)

[Schmell]

Originally Posted by John in Santa Cruz

for dealing with GC-2/T105 golf cart batteries it really helps to have a golf cart battery strap, thi sis a handle that clips onto those two square lugs on the top of the batt. you can see this strap/handle sitting on top of the old battery box here...





I swapped my GC batts without disconnecting or covering my old 160W stock solar panel with the GoPower PWM controller as at the time I wasn't aware that was recommended practice. When I installed my much larger 360W solar panel with a MPPT controller, I added a solar cutoff switch near the controller to make maintenance easier.

I always disconnect the negative terminal first, then the bridging cable, then the positive cable, then lift each batt out, place the new ones in, and reconnect in the opposite order (+ first, then the bridge cable, then the -)

Thank you John, this is very helpful. I assume you are saying the negative terminal first, then the bridging cable from the Negative post? Then the positive.



I've never done anything like this before, so I guess I just have to be super careful that the cables don't touch anything, and I need to find a big strong person to lift out the batteries for me