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RV house battery
- Thread starter timtune
- Start date
2 6v golf cart batteries in series will outperform anything else aside from lithium, and they are a drop in replacement if you have the room. They are *true* deep cycle batteries unlike a lot of 12v "deep cycle" batteries which are actually hybrids - good point of reference is if it has a cranking amps rating, it's not a true deep cycle. These are designed for mix uses like boats where they may be used for house loads and bilge pumps or trolling motors, but still needed for starting engines as well.
A true deep cycle will not have a starting/CCA rating.
I used to have a bank of 4 6v golf cart batteries in the front of our 5th wheel and we could use power with reckless abandon (including heavy use of the inverter to avoid running the generator) for days or weeks at a time.
Princess Auto has these which are honestly a pretty awesome deal:
If your budget is much higher, go lithium. For house loads it's impossible to beat, and since they can be drawn down to a drastically lower SOC (near zero, whereas a lead acid should never be drawn down below 50% SOC) you can buy a battery that's technically half the amp hours and get just as much capacity out of it in the end. And they're a fraction of the weight as well. Or buy a big one and live with reckless abandon - still drastically lighter than a SLA battery.
Just be sure if you go lithium to buy one with built in charge management circuitry so that it'll play nice with the very dumb low-tech converter/chargers in most RV's.
A true deep cycle will not have a starting/CCA rating.
I used to have a bank of 4 6v golf cart batteries in the front of our 5th wheel and we could use power with reckless abandon (including heavy use of the inverter to avoid running the generator) for days or weeks at a time.
Princess Auto has these which are honestly a pretty awesome deal:
If your budget is much higher, go lithium. For house loads it's impossible to beat, and since they can be drawn down to a drastically lower SOC (near zero, whereas a lead acid should never be drawn down below 50% SOC) you can buy a battery that's technically half the amp hours and get just as much capacity out of it in the end. And they're a fraction of the weight as well. Or buy a big one and live with reckless abandon - still drastically lighter than a SLA battery.
Just be sure if you go lithium to buy one with built in charge management circuitry so that it'll play nice with the very dumb low-tech converter/chargers in most RV's.
Your road trek has a space built for lead acid and does not have room for two 6v . It’s very hard to beat a CTC marine deep cycle when it’s on sale , or Costco or Princess auto , somebody always has one on sale .
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Depends on how long you will be off-grid for. I replaced the lead acid battery in my new trailer with a Lithium battery and now I can be 3 days off-grid compared to about 18-20 hours with the lead acid. And that’s with running a residential size fridge/freezer, water pump and lights.
Lithium is pricey, but it buys you the extra time. If you don’t need that extra time, save yourself the money and get a good lead acid.
Lithium is pricey, but it buys you the extra time. If you don’t need that extra time, save yourself the money and get a good lead acid.
You can run a residential size fridge 3 days on a lithium battery? That’s out standing . I can’t get much beyond 24hr with a 12v compact fridge on one battery .
One thing for regular folk to consider putting lithium into a spot where lead acid used to live , make sure you have venting / cooling sorted out and a battery monitor to shut down power draw if the battery over heats . The lithium batteries seem to over heat more often during discharge than recharge , they have been linked to a few fires .
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One thing for regular folk to consider putting lithium into a spot where lead acid used to live , make sure you have venting / cooling sorted out and a battery monitor to shut down power draw if the battery over heats . The lithium batteries seem to over heat more often during discharge than recharge , they have been linked to a few fires .
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I just picked up a deep cycle marine battery at Costco yesterday. item #207200
Was supposed to be $139.99 plus $10 core charge.
Once I checked out the receipt there was a $30 discount for some reason. Nice surprise.
Funny thing is that on Saturday I could stil see the product on the Costco site even though it said "warehouse only". On sunday item is not longer on the site.
Maybe these are seasonal for them and were on sale.
Deep cycle/lawn teactor Batteries normally get cleared out of costco at end of season ($xxx.97 is the easy way to tell they are dumping them)
Just checked again. No $xx.97 on the original price . Just a seperate line with item #1691858
@ $30.00-.
They had approx 25 in stock at Dixie and Dundas location
Oh yes. Well aware of their $xx.97 tactic.
What actually causes the fire is not overheating but actually over-charging. Lithium batteries are a bunch of small 3V batteries in parallel/series. (there are 6 small batteries in series inside of your 2AH drill battery pack for instance) A Battery Monitoring system will work to keep things even (among other things). If 5 cells are at 2.5V and one is at 3V then you only have 15.5V. If your BMS is bypassed or non-exhistant, then you charge to18V, that outlier has a chance of being overcharged and on-fire. As you add parallel branches it gets harder to detect a single failing cell.
Before building my battery packs I checked out some youtube videos of Russians trying to destructive test lithium batteries. They are way tougher then people make them out to be. Locking pliers across the top and bottom terminal was the only real big bang.
NFPA doesn't entirely agree. Discharge can hurt batteries and cause a thermal runaway. A battery explosion probably causes less damage than a raging fire.
"For most cells , discharge below 3.0 V can cause degradation of electrodes and thus discharge below the manufacturer’s low voltage specification is referred to as over-discharge. Repeated over-discharge can lead to cell failure and cell thermal runaway (discussed below). For most cells, charging significantly above 4.2 V (e.g., to 5 V) can lead to rapid, exothermic degradation of the electrodes"
"High rate discharges can cause heating of cells, in some cases to the point of damaging internal components such as the separator, and can lead to cell thermal runaway."
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Thanks all. Unfortunately @crankcall is correct - no room for two golf cart batteries or I would go that route and my old charging inverter system may not play nice with lithium. For now I'm going old's cool and see what kind of off grid time I can get with a fresh battery. Maybe lithium down the road.......
There are some pretty sweet solar panel setups availble now that can increase your off grid range to almost indefinate. You can get the A frame style you set up beside where your parked , my favorite is the roof systems which arent perfect as they dont lean into the sun , but they are woirking all the time. If there was ever a case of get what you pay for its with solar panels and controllers.
But figure out what you need / want , and do that. I see a lot of installations where they have built a system that can go months , but they are never off grid more than 36hrs.
My deep cycle 12v conventional style gets me about 24hrs of running a 12v cooler, some electronic instruments and some low draw lighting. Then I'm either charging off the engine or plugged into 120V.
FWIW, you can also overcharge and start a fire with a conventional 12v deep cycle if you have cheap onboard chargers on an RV, but you have to try harder.
But figure out what you need / want , and do that. I see a lot of installations where they have built a system that can go months , but they are never off grid more than 36hrs.
My deep cycle 12v conventional style gets me about 24hrs of running a 12v cooler, some electronic instruments and some low draw lighting. Then I'm either charging off the engine or plugged into 120V.
FWIW, you can also overcharge and start a fire with a conventional 12v deep cycle if you have cheap onboard chargers on an RV, but you have to try harder.
I didn't say that over discharge can't hurt batteries. I said that the common issue causing fire is on charging, and that its often due to lack of a BMS which most professional batteries (that aren't bought online from China) have.
Good job on googling the exact voltages. I was just using the nominal numbers because that voltage changes with battery chemestry. My LiFEPo4 batteries go down to 2.5V just fine for instance But can only take 3.5V. I generally refer to the battery in my bike as a 12V battery not a 13.6V battery or whatever it's max is before it starts on fire.
Jeebus you're pissy about this. I didn't google anything. That was a direct quote from the linked NFPA research paper on battery fires. In response to someone saying that they can burn during discharge, you implied that over-charging is responsible for all lithium battery fires. That statement is proven to be false by the paper.
The trailer has a small solar panel on the roof which I’m sure helps with battery life.
If you want the specs on the trailer just Google Grey Wolf 22RR with the optional juice pack.
Costco near me has all batteries on sale. Most ~$30 off. They had the deep cycle you got and a larger one for 180-30 iirc.
Battery life can be very dependent on how it was used/maintained. Abuse it and capacity may be way down after a year. If you get over five years with decent capacity left you are doing well imo.
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