Let's talk batteries.

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CafeRoaster

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Enthusiast III

473
Seattle, WA, USA
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David
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Clark
I am on the hunt for a battery that can handle at least some load when the vehicle is off. I have a dash cam with parking mode that killed my current Walmart battery (it was a temporary anyways while I build my rig). That battery fails to start every now and then, and is just so sluggish to start every time. So I'd really like to get the battery I'll need when I have more electrical to run.

It seems like everyone you ask, they just say to get Optima Yellowtop, but if you ask people a year or two later, they'll tell you it died, unless they're running a dual battery setup.

So do I just admit defeat and just get a strong starting battery and figure out electrical later, or is there actually a battery out there that is truly dual purpose?
 

K12

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I am on the hunt for a battery that can handle at least some load when the vehicle is off. I have a dash cam with parking mode that killed my current Walmart battery (it was a temporary anyways while I build my rig). That battery fails to start every now and then, and is just so sluggish to start every time. So I'd really like to get the battery I'll need when I have more electrical to run.

It seems like everyone you ask, they just say to get Optima Yellowtop, but if you ask people a year or two later, they'll tell you it died, unless they're running a dual battery setup.

So do I just admit defeat and just get a strong starting battery and figure out electrical later, or is there actually a battery out there that is truly dual purpose?
Optima batteries are awesome for your car. Most car batteries are not made to continually drain, and need a vast majority of their charge to start the vehicle back up. This is why a dual battery setup is better. The alt batter is for all the electronics and will power then the car is on, but there is no drain on the main so you know your vehicle will start.

What you need to figure out is how much stuff you want to power, the power draw, and length of time you are running it. For example if you want some pod lights hooked up to the battery running all night to light up the camp ground, you will likely need that second battery.
 

CafeRoaster

Rank II

Enthusiast III

473
Seattle, WA, USA
First Name
David
Last Name
Clark
I am on the hunt for a battery that can handle at least some load when the vehicle is off. I have a dash cam with parking mode that killed my current Walmart battery (it was a temporary anyways while I build my rig). That battery fails to start every now and then, and is just so sluggish to start every time. So I'd really like to get the battery I'll need when I have more electrical to run.

It seems like everyone you ask, they just say to get Optima Yellowtop, but if you ask people a year or two later, they'll tell you it died, unless they're running a dual battery setup.

So do I just admit defeat and just get a strong starting battery and figure out electrical later, or is there actually a battery out there that is truly dual purpose?
Optima batteries are awesome for your car. Most car batteries are not made to continually drain, and need a vast majority of their charge to start the vehicle back up. This is why a dual battery setup is better. The alt batter is for all the electronics and will power then the car is on, but there is no drain on the main so you know your vehicle will start.

What you need to figure out is how much stuff you want to power, the power draw, and length of time you are running it. For example if you want some pod lights hooked up to the battery running all night to light up the camp ground, you will likely need that second battery.
So then my follow-up inquiry would be:
- Is a Yellowtop worth it or just get a strong Redtop?
- If a Redtop is enough, why not just another brand AGM?

I would think if I do end up getting a fridge and lights, I would want to figure out a second power setup for those. For the vehicle itself, I really just need a strong starter that can run basic accessories - dash cam that’s hardwired instead of 12v DC outlet and can run parking mode, new dual DIN head unit with screen. I can’t really think of anything else I’d run on the car battery. But I’m also very new to all this and have never been great with electrical, so I may not be planning accurately.
 

K12

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I am on the hunt for a battery that can handle at least some load when the vehicle is off. I have a dash cam with parking mode that killed my current Walmart battery (it was a temporary anyways while I build my rig). That battery fails to start every now and then, and is just so sluggish to start every time. So I'd really like to get the battery I'll need when I have more electrical to run.

It seems like everyone you ask, they just say to get Optima Yellowtop, but if you ask people a year or two later, they'll tell you it died, unless they're running a dual battery setup.

So do I just admit defeat and just get a strong starting battery and figure out electrical later, or is there actually a battery out there that is truly dual purpose?
Optima batteries are awesome for your car. Most car batteries are not made to continually drain, and need a vast majority of their charge to start the vehicle back up. This is why a dual battery setup is better. The alt batter is for all the electronics and will power then the car is on, but there is no drain on the main so you know your vehicle will start.

What you need to figure out is how much stuff you want to power, the power draw, and length of time you are running it. For example if you want some pod lights hooked up to the battery running all night to light up the camp ground, you will likely need that second battery.
So then my follow-up inquiry would be:
- Is a Yellowtop worth it or just get a strong Redtop?
- If a Redtop is enough, why not just another brand AGM?

I would think if I do end up getting a fridge and lights, I would want to figure out a second power setup for those. For the vehicle itself, I really just need a strong starter that can run basic accessories - dash cam that’s hardwired instead of 12v DC outlet and can run parking mode, new dual DIN head unit with screen. I can’t really think of anything else I’d run on the car battery. But I’m also very new to all this and have never been great with electrical, so I may not be planning accurately.
I had an optima red top when I had my car and my old truck and never had any problems. My truck had pod lights, air compressor, charged my Goal Zero power station and some other stuff. If anything was run with the vehicle off it was minimal. But never had a probelm and had the batteries for years.

Might want to make sure your alternator is keeping up?
 

CafeRoaster

Rank II

Enthusiast III

473
Seattle, WA, USA
First Name
David
Last Name
Clark
I am on the hunt for a battery that can handle at least some load when the vehicle is off. I have a dash cam with parking mode that killed my current Walmart battery (it was a temporary anyways while I build my rig). That battery fails to start every now and then, and is just so sluggish to start every time. So I'd really like to get the battery I'll need when I have more electrical to run.

It seems like everyone you ask, they just say to get Optima Yellowtop, but if you ask people a year or two later, they'll tell you it died, unless they're running a dual battery setup.

So do I just admit defeat and just get a strong starting battery and figure out electrical later, or is there actually a battery out there that is truly dual purpose?
Optima batteries are awesome for your car. Most car batteries are not made to continually drain, and need a vast majority of their charge to start the vehicle back up. This is why a dual battery setup is better. The alt batter is for all the electronics and will power then the car is on, but there is no drain on the main so you know your vehicle will start.

What you need to figure out is how much stuff you want to power, the power draw, and length of time you are running it. For example if you want some pod lights hooked up to the battery running all night to light up the camp ground, you will likely need that second battery.
So then my follow-up inquiry would be:
- Is a Yellowtop worth it or just get a strong Redtop?
- If a Redtop is enough, why not just another brand AGM?

I would think if I do end up getting a fridge and lights, I would want to figure out a second power setup for those. For the vehicle itself, I really just need a strong starter that can run basic accessories - dash cam that’s hardwired instead of 12v DC outlet and can run parking mode, new dual DIN head unit with screen. I can’t really think of anything else I’d run on the car battery. But I’m also very new to all this and have never been great with electrical, so I may not be planning accurately.
I had an optima red top when I had my car and my old truck and never had any problems. My truck had pod lights, air compressor, charged my Goal Zero power station and some other stuff. If anything was run with the vehicle off it was minimal. But never had a probelm and had the batteries for years.
I kept my engine running while inflating during my first trip out. Wasn’t sure if that’s normal or not, but I knew my battery couldn’t handle it without the engine running. Is that normal?

So it sounds like you’re saying that since most items are charged or operated while the vehicle is on, maybe don’t stress about it too much?
 

danwyandt

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I have a Optima RedTop for starting, dash stuff, etc. A 2nd Optima BlueTop/deep cycle for powering the Winch, trans cooler and SwitchPros system for lighting. 2 more BlueTops in back for Compressor, Fridge, USB charge ports, 4k 110v ac inverter, and the 750w stereo amps. Run that all through a 3-way Isolator with a 250 amp alternator.
Sorry, I know it's a bit over the top, but it's better (for me anyway) than heroin :)
-Dan
 

genocache

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9 years ago I bought a Sears, Platmium AGM deepcycle, the largest one I could fit in my battery tray. I have a dash cam and every time the Rover is bumped it comes on. The battery is still there. Since it's my daily driver the battery stays charged though during the pandemic the amount of driving dropped to once or twice a month for groceries.

UPDATE; I just went out and looked, it's a group 31M battery with 1150 CCA.
 
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OTH Overland

Local Expert Washington, USA
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Batteries are designed for many purposes, a starting battery that comes with the vehicle has one main purpose, starting the car. On a cold day with thick engine oil it takes a lot of amperage to crank the engine over. a starting battery can produce a lot of amps for a short time, then gets replenished by the alternator while you are driving to the grocery store. What they are really bad at is delivering low amperage for long periods of time down to a low level of charge, such as running a fridge or camp lights all night. Each time they recover a little less of their capacity when recharging. Diesel pickups have dual starting batteries as they take that much more power when starting. RV's use deep cycle batteries that are designed to be used on low amperage loads and recharged often, however pulling a large starting load on them regularly kills them off. My preference has always been to leave the vehicles electrical system and batter as stock as I can because it it well designed for what it does, then add a deep cycle battery or lithium battery somewhere in the vehicle and use that for all my accessory loads. Installing a battery isolator between them prevents any one battery from draining the other (or if you want to get fancy you can use battery manager system that can charge the second battery from the alternator, house power, or solar.) I don't worry about connecting the batteries together in case the engine battery goes dead, just carry a portable jump pack. advantage with this system is using the batteries as they are intended, and if something goes wrong with your secondary electrical system, you can just disconnect one wire and leave the factory wiring intact to get you home. Most importantly check the specs on your batteries to know what the lowest recommended level of charge is, some should only go down to 50% before becoming susceptible to damage.
 

lhoffm4

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I recommend doing a use analysis and build your battery bank accordingly. I also recommend separating the starting system for your vehicle drone your accessory system. If you think you might ever consider adding Solar to your kit, I recommend looking up Will Prouse and his DIY Solar website. They have a usage calculator that will tell you what electrical components draw. You can list what you have/plan to have and it will tell you what you should build up to. You can scale it up as needed. There are suggestions for components and there are several pre-configured setups with diagrams price lists, where to buy, etc.

My best advise is to make your dream configuration and build a modular/scalable system. For example, I started with my list of needs and decided on a LiFePO4 12v/ 200ah battery. A 100ah solar panel a charge controller and a 2000Watt inverter. With some searching I was able to get everything for less than $500. A cost savings of at least $1500, for what I put together. I can add panels and more batts as time goes on, if my system needs to grow from my camp trailer to an rv or even a back up plan for my home, it can grow.

starting out with a minimum list of your power needs is the best first step.
 

CafeRoaster

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473
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Fantastic explanation, and I think I agree with your opinion of leaving the system as stock as possible.

I recommend doing a use analysis and build your battery bank accordingly. I also recommend separating the starting system for your vehicle drone your accessory system. If you think you might ever consider adding Solar to your kit, I recommend looking up Will Prouse and his DIY Solar website. They have a usage calculator that will tell you what electrical components draw. You can list what you have/plan to have and it will tell you what you should build up to. You can scale it up as needed. There are suggestions for components and there are several pre-configured setups with diagrams price lists, where to buy, etc.

My best advise is to make your dream configuration and build a modular/scalable system. For example, I started with my list of needs and decided on a LiFePO4 12v/ 200ah battery. A 100ah solar panel a charge controller and a 2000Watt inverter. With some searching I was able to get everything for less than $500. A cost savings of at least $1500, for what I put together. I can add panels and more batts as time goes on, if my system needs to grow from my camp trailer to an rv or even a back up plan for my home, it can grow.

starting out with a minimum list of your power needs is the best first step.
Do you have a link for that site? I found his business site and the forum, but no calculator.
 

lhoffm4

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Fantastic explanation, and I think I agree with your opinion of leaving the system as stock as possible.



Do you have a link for that site? I found his business site and the forum, but no calculator.
I don't off hand, but if you do a search for off grid power calculator or usage calculator, it should send you where you want to go. The one I found was an excel spreadsheet.
 

Viking1204

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I have an X2 Power Dual Purpose/Deep Cycle battery in my truck. It has 930 CCA and 90AH so it won't go dead if I leave the radio or a light on for a bit! I've actually left a cab light on overnight and it still cranked in the morning. I only paid about $300 when I bought mine but like everything else they've gone up in price.

X2Power BCI Group 27M 12V 930CCA AGM Marine & RV Battery - SLI27AGMDPM
 

North American Sojourner

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Batteries are designed for many purposes, a starting battery that comes with the vehicle has one main purpose, starting the car. On a cold day with thick engine oil it takes a lot of amperage to crank the engine over. a starting battery can produce a lot of amps for a short time, then gets replenished by the alternator while you are driving to the grocery store. What they are really bad at is delivering low amperage for long periods of time down to a low level of charge, such as running a fridge or camp lights all night. Each time they recover a little less of their capacity when recharging. Diesel pickups have dual starting batteries as they take that much more power when starting. RV's use deep cycle batteries that are designed to be used on low amperage loads and recharged often, however pulling a large starting load on them regularly kills them off. My preference has always been to leave the vehicles electrical system and batter as stock as I can because it it well designed for what it does, then add a deep cycle battery or lithium battery somewhere in the vehicle and use that for all my accessory loads. Installing a battery isolator between them prevents any one battery from draining the other (or if you want to get fancy you can use battery manager system that can charge the second battery from the alternator, house power, or solar.) I don't worry about connecting the batteries together in case the engine battery goes dead, just carry a portable jump pack. advantage with this system is using the batteries as they are intended, and if something goes wrong with your secondary electrical system, you can just disconnect one wire and leave the factory wiring intact to get you home. Most importantly check the specs on your batteries to know what the lowest recommended level of charge is, some should only go down to 50% before becoming susceptible to damage.
Okay, so your name is Dave and so is mine and I swear you're my brother of something. LOL. This is the best explanation of a dual battery system I've ever heard, and basically straight out of my mouth. Thank you for that. Now when do we start our company? LMAO
Zim
 
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OTH Overland

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Okay, so your name is Dave and so is mine and I swear you're my brother of something. LOL. This is the best explanation of a dual battery system I've ever heard, and basically straight out of my mouth. Thank you for that. Now when do we start our company? LMAO
Zim
Hard part will be deciding which one of our names we would list first in the name... lol
 

ThundahBeagle

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Okay, so your name is Dave and so is mine and I swear you're my brother of something. LOL. This is the best explanation of a dual battery system I've ever heard, and basically straight out of my mouth. Thank you for that. Now when do we start our company? LMAO
Zim
Like Tom & Tom, the juice guys from Nantucket Nectar. But with batteries. And the name Dave. Ok, its completely different
 

Shakes355

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As a note, switching to an AGM or Li battery is very dependent on the vehicle you drive if you rely solely on the alternator for recharging. Lead acid batteries get a bad rep for a lot of justified reasons, but they love to take amperage and charge very quickly from lower voltages. AGMs on the other hand don't.

Li can take a decent amount of juice, but they operate at a higher voltage than a standard voltage regulator would provide in factory form.

Without getting down in the weeds, I guess my point is that you should ensure you have a battery management system designed for the type you choose. Otherwise you could end up getting a significantly shorter life span out of the investment.
 

DMS1

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Optima batteries are not as good as they use to be. I recommend Odyssey batteries, my last one lasted 6 years with no issues.
 

CafeRoaster

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As a note, switching to an AGM or Li battery is very dependent on the vehicle you drive if you rely solely on the alternator for recharging. Lead acid batteries get a bad rep for a lot of justified reasons, but they love to take amperage and charge very quickly from lower voltages. AGMs on the other hand don't.

Li can take a decent amount of juice, but they operate at a higher voltage than a standard voltage regulator would provide in factory form.

Without getting down in the weeds, I guess my point is that you should ensure you have a battery management system designed for the type you choose. Otherwise you could end up getting a significantly shorter life span out of the investment.
Oh! I thought on Lithium Ion batteries had this issue.

Could you direct me to some weeds to get into? I was really considering an AGM. There is one AGM that I know works with a factory setup, but I don't know if it would be good for what I want to setup.