Any issues with 4 12 volt batteries?
Just purchased a new toy hauler. Has 2 new 12 volt batteries installed. Right before i sold my other trailer i purchased 2 12 volt batteries. I want to run all 4. When they die, i will swap them out...
Forum Discussion
LOWSUV - Its just a matter of cost actually for 12VDC batteries verses 6VDC batteries and how much AHs capacity you want to have.
In my case I was originally going for four GP24 batteries since I already had two of them when I got the trailer. That would have gave me around 340AHs battery capacity for a $180 additional investment getting a couple more GP24 12VDC 85AH Interstate batteries.
The GP24 GC2 COSTCO 6VDC batteries on the other hand will give you 220AHs battery capacity with two 6VDC batteries in series and you can increase that to 440AHs capacity getting another series setup and running those two groups in parallel with each other. These GC2 6VDC batteries are around $80 each from COSTCO. Getting a 440AH 12VDC battery bank for $320 is a pretty good deal especially when you consider the RESERVE POWER of the GC2 6VDC batteries. The series/parallel configuration of the four GC2 6VDC batteries will give you a good 14 hours or more of RESERVE POWER. By comparison running the four each GP24 85AH Interstate batteries in parallel will only give 12VDC at around 9 hours of RESERVE power.
RESERVE POWER is rated for most batteries of how long the battery will produce 12VDC@25AMPS until the battery drops below 10.5VDC or 0% charge state. Of course you never want want to draw down your batteries below the 50% charge state so you can really only count of half the RESERVE POWER rate listed.
All these numbers just make my head spin so I planned everything out by trial and error and added enough batteries to run all of the 120VAC things I wanted to run from an Inverter and 12VDC items direct connected to the battery bank so that my battery bank would be at around 12.0VDC at 8Am he next morning. Then during breakfast I will connect my trailer to my 2KW Generator 120VAC receptacle using a RV30A-15A adapter and recharge my battery bank back up to its 90% charge state with a three hour generator run time. This usually fits in just fine with the campgrounds that have generator run time restrictions in place. Once my batteries are back up to their 90% charge state then I can do this all over again for the next day/night run off the batteries. I have found out I can do around 12 days or so of these 50% to 90% cycles on my battery bank before I start losing performance (Not holding their charge as expected). Then I have to do a full 100% charge state which in my case requires around 12 hours of charge time. Sometimes I have had to do two of the 100% charge state runs to get the batteries back their good expected long term holding their charge. Most camp grounds we go to I am not allowed to run my generator that long on a continuous basis.
This is where having solar panels would be a big help in my way of camping off the power grid as I can use the HIGH SUN hours to continue getting the batteries charged after the generator has been shut down. To get full charging performance from solar panels in my case i would have to have a SOLAR usable output of 14.4VDC@15-20AMPS of DC current for each battery in the battery bank to obtain a quick thee hour battery re-charge. Most 120WATT Solar panels will only produce 5-6AMPS of DC Current so you can see the short fall here just relying on the solar panels to rec-charge your batteries. You definitely won't get the quick three hour charge time from 50% to 90% charge state but you might be able to get to the 90% charge with 8-10 hours of HIGH SUN charge time with just maybe three 120WATT Solar panels that would be producing 14.4VDC@18 DC AMPS or so during the high sun time.
In my case with what we want to have running when off the power grid I will have to start my re-charge of the battery banks using my generator for the first hours or so to get over the high current portion of the battery charge period and switch to solar panels to finish the complete re-charge state when the batteries want to see the 13.6VDC at 6-8AMPS of DC charge to get to the 90%-100% charge state..
Guys are already telling me I may be thinking this too hard so will have to install things and do the trial and error method to get the job done on my new 300AH Trojan T1275P battery banks I want to build up. One being in the back of my truck bed and the other one on the trailer tongue area. I will connect these together when in camping mode (600Ahs).
With my HAM RADIO SETUP I probably will use more DC power when camping as compared to the casual camping experience off the power grid.
Its all in the planning haha... I'm sure I will have a couple of get dark periods at 10PM nights before I figure it all out and can claim being successful like we are at the moment with our present way of charging batteries using the 2KW generator. This is what my CAMP BACKYARD spot is for. I also have a nice camp ground just 40 miles from here at Westmoreland State park where I can make camping runs in full test mode learning all the things I need to know. If it gets dark on me I can just go home haha...
Roy Ken
In my case I was originally going for four GP24 batteries since I already had two of them when I got the trailer. That would have gave me around 340AHs battery capacity for a $180 additional investment getting a couple more GP24 12VDC 85AH Interstate batteries.
The GP24 GC2 COSTCO 6VDC batteries on the other hand will give you 220AHs battery capacity with two 6VDC batteries in series and you can increase that to 440AHs capacity getting another series setup and running those two groups in parallel with each other. These GC2 6VDC batteries are around $80 each from COSTCO. Getting a 440AH 12VDC battery bank for $320 is a pretty good deal especially when you consider the RESERVE POWER of the GC2 6VDC batteries. The series/parallel configuration of the four GC2 6VDC batteries will give you a good 14 hours or more of RESERVE POWER. By comparison running the four each GP24 85AH Interstate batteries in parallel will only give 12VDC at around 9 hours of RESERVE power.
RESERVE POWER is rated for most batteries of how long the battery will produce 12VDC@25AMPS until the battery drops below 10.5VDC or 0% charge state. Of course you never want want to draw down your batteries below the 50% charge state so you can really only count of half the RESERVE POWER rate listed.
All these numbers just make my head spin so I planned everything out by trial and error and added enough batteries to run all of the 120VAC things I wanted to run from an Inverter and 12VDC items direct connected to the battery bank so that my battery bank would be at around 12.0VDC at 8Am he next morning. Then during breakfast I will connect my trailer to my 2KW Generator 120VAC receptacle using a RV30A-15A adapter and recharge my battery bank back up to its 90% charge state with a three hour generator run time. This usually fits in just fine with the campgrounds that have generator run time restrictions in place. Once my batteries are back up to their 90% charge state then I can do this all over again for the next day/night run off the batteries. I have found out I can do around 12 days or so of these 50% to 90% cycles on my battery bank before I start losing performance (Not holding their charge as expected). Then I have to do a full 100% charge state which in my case requires around 12 hours of charge time. Sometimes I have had to do two of the 100% charge state runs to get the batteries back their good expected long term holding their charge. Most camp grounds we go to I am not allowed to run my generator that long on a continuous basis.
This is where having solar panels would be a big help in my way of camping off the power grid as I can use the HIGH SUN hours to continue getting the batteries charged after the generator has been shut down. To get full charging performance from solar panels in my case i would have to have a SOLAR usable output of 14.4VDC@15-20AMPS of DC current for each battery in the battery bank to obtain a quick thee hour battery re-charge. Most 120WATT Solar panels will only produce 5-6AMPS of DC Current so you can see the short fall here just relying on the solar panels to rec-charge your batteries. You definitely won't get the quick three hour charge time from 50% to 90% charge state but you might be able to get to the 90% charge with 8-10 hours of HIGH SUN charge time with just maybe three 120WATT Solar panels that would be producing 14.4VDC@18 DC AMPS or so during the high sun time.
In my case with what we want to have running when off the power grid I will have to start my re-charge of the battery banks using my generator for the first hours or so to get over the high current portion of the battery charge period and switch to solar panels to finish the complete re-charge state when the batteries want to see the 13.6VDC at 6-8AMPS of DC charge to get to the 90%-100% charge state..
Guys are already telling me I may be thinking this too hard so will have to install things and do the trial and error method to get the job done on my new 300AH Trojan T1275P battery banks I want to build up. One being in the back of my truck bed and the other one on the trailer tongue area. I will connect these together when in camping mode (600Ahs).
With my HAM RADIO SETUP I probably will use more DC power when camping as compared to the casual camping experience off the power grid.
Its all in the planning haha... I'm sure I will have a couple of get dark periods at 10PM nights before I figure it all out and can claim being successful like we are at the moment with our present way of charging batteries using the 2KW generator. This is what my CAMP BACKYARD spot is for. I also have a nice camp ground just 40 miles from here at Westmoreland State park where I can make camping runs in full test mode learning all the things I need to know. If it gets dark on me I can just go home haha...
Roy Ken
