Looking to invest in battery system and need some help... (1 Viewer)

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filer5000

filer5000

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Hi guys! As the title says, I'm looking to install a battery system in my 100 series used for camping (powering diesel heater, fridge, lights and maybe a fan). One of my buddies had an EcoFlow power bank, which works well but we can only do about a night of camping on a full charge. I also want to be able to build it into my system and be able to charge the battery off my alternator while the car is running. I also want to get something with heating and good bluetooth management.

So here are the things I'm looking for:
- about 100Ah
- built in heat
- able to charge off of alternator

I've been looking at the Epoch Batteries one but I'm wanting to see your guys' suggestions.
 
Check out my install of a 100ah mini
forum.ih8mud.com

Victron DC/DC charger install ARB Drawers

I have been running my ARB 50L and other electronics off of an X2 Power 27F for a couple of years now with great results. A 6 awg cable runs from the breaker thru the firewall and terminated at the Blue Sea fuse pack mounted to the face of the ARB drawers. Recently the 27F maintained the fridge...
forum.ih8mud.com forum.ih8mud.com
 
Identify your demand usage over time... and work from there regarding battery amperage size/capacity. If you will be using your battery in colder, near/below freezing just know you won't get the same output efficiency compared to warmer ambient climes...factor this in to your current needs.

LiTime seems to be one of the low priced leaders right now but I know nothing about their after-sale support if/when needed: https://www.litime.com/

The new Victron Orion XS is the bomdigity. Small form factor, 98% efficient (which means less heat output), Bluetooth, easily customizable charge perimeters, serves as an isolator, blah blah blah; worth the coin.
 
Adding to the info above:
I use, sell and have installed lots of Dakota Lithium and Deep Cycle Systems Lithium batteries at my shop. Both brands have top support and quality construction with proprietary BMS and cells. They also have built in heating and Bluetooth monitoring with reliable apps. They also have the ability to crank an engine in an emergency start scenario.

Find or make a space where you plan to mount the battery and check dimensions and go from there. Dakota makes a 135ah in a Group 24 size. Deep Cycle Systems has their super slim 120ah at only 2” thin. That battery is the most advanced drop in Lithium now with thermal resin and passive cooling, very similar in temperature management to hybrid battery systems in cars. 120Ah Slimline Deep Cycle LFP Battery - https://deepcyclesystems.us/products/12v-120ah-super-slim-deep-cycle-lfp-battery

You’re not gonna want to charge any LiFePo4 directly off an alternator. You’ll need to charge it via solar and/or DC to DC charging.
 
To be fair, relying on the alternator to soley/directly supply proper voltage to FLA, LA, LFP, etc., isn't in the best interest of getting the maximum life and dependability out of the battery/batteries. Yes, the diode trick helps. But IMO, incorporating a DC-DC charger is in the best interest to maximizing performance and longevity of said battery/batteries. Just be sure to right-size the alternator's output capability relative to the maximum current flow of the DC-DC charger...
 
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^
I would also go the DC-DC route because that gives me full control but I don't see big problems -at least theoretically- with charging a 12V LFP battery directly with the alternator/starting battery system in the 100 in a pinch, assuming the alternator does not go over 14.6V. At the usual 14.4V you are way up there in voltage for the LFP already. It's basically fully charged at that point. Yes, you ideally want to isolate the secondary battery and all that, but if that kind of charging is not 100% optimal, it seems at least safe to me. What am I missing here?
 
I am not getting 14.4v out of my 100 or my LBZ with stock alternators. For the price of entry for a Victron Orion XS it serves as isolator, multi-chemistry battery charger with a very customizable output, etc., etc. and has an easy BT interface. Also I recommend incorporating a Victron/favorite brand smart shunt to be able to see real time current in/out of the battery, etc.

FWIW/FYI, I'm running a 100A alternator on my 100 and, generally, the max current output on the Orion has been in the 35A +/- range. Whereas the stock alternator (145A) alternator on the LBZ allows the Orion XS to run, typically, between 47-49A.
 
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I do get close to 14.4V out of our 100 alternator. Is there an issue with your voltage regulation, maybe?
But anyway, 35A is not bad at all for this kind of work. I'd rather go easy on my batteries than too hard, if not in a major hurry.
 
DC-DC chargers are needed in most cases when using alternators to charge batteries. Without a DC-DC charger, an alternator’s power output can charge the battery at a rate more than 1C, which causes damage to the battery and may turn the battery off by triggering the overcharging protection in the battery management system (BMS). Also, charging a large capacity ‘house bank’ of batteries via the alternator will cause it to
run at full nameplate output power, which may overheat and/or damage the alternator.

Direct to alternator charging also can’t put out the specific voltage needed to charge a LiFePo4 battery to 100%. You’ll typically only get around 80% charge max.
 
Good info here. My house battery runs on its own old-school (not smart) 60A alternator. Was planning on plunking a LIFePo4 straight in place of the agm I have in there now. Was going to add a Victron controller when I get around to adding a small solar set up.
 
^^ @Shoredreamer, I would use a DC-DC myself, but for the sake of the discussion, I feel I should also add that whereas what you say is true in theory, I doubt that the 1C issue or overtaxing the alternator would be an issue in real life with a LC100 alternator and one typical 100Ah house battery with a 100A BMS, if that battery is installed in parallel with the starting battery (not that I would recommend the latter).
Also, not trying to be overly argumentative, but I would think that the usual 14+V charging would give you well above a 80% charge on an LFP battery. The LFP battery running this very computer is 85% charged at a bit under 13.5V right this instant.

But I've been plenty wrong before, so...
 
e9999 said:
^^ @Shoredreamer, I would use a DC-DC myself, but for the sake of the discussion, I feel I should also add that whereas what you say is true in theory, I doubt that the 1C issue or overtaxing the alternator would be an issue in real life with a LC100 alternator and one typical 100Ah house battery with a 100A BMS, if that battery is installed in parallel with the starting battery (not that I would recommend the latter).
Also, not trying to be overly argumentative, but I would think that the usual 14+V charging would give you well above a 80% charge on an LFP battery. The LFP battery running this very computer is 85% charged at a bit under 13.5V right this instant.

But I've been plenty wrong before, so...
Click to expand...
No worries, I appreciate the discussion. My remarks come from the 2 battery manufacturers who make these lithium batteries with engine starting potential. I don’t have any personal experience running a LiFePo4 directly to an alternator as a house or start battery on any of my vehicles and of the many installs I’ve done I’ve never wired a LiFePo4 directly to an alt, always thru a DC to DC. Additionally there are very few people I have found who have done lithium direct to alt either. It still seems to be in the Guinea pig stage to run either lithium as a start battery or charging a lithium direct to an alternator. This could be either because of the inherent risks and trade offs vs doing a DC to DC.
 
Yes, no doubt it's better to have the control features of a DC-DC charger. But I probably would not hesitate too much on a direct connection either, if I were in a tight spot or could not afford to buy a dedicated charger, just not seeing a big downside to that at this time.
 
FWIW, I purchased a 200A LFP "drop-in" battery from Affordable Electric Vehicle Batteries & Components from Electric Car Parts Company - https://www.electriccarpartscompany.com/ in 2016 and its been connected direct to alternator in either the then little trailer or for the past 7-years, in the bed of my '07 Silverado. I have no idea if the battery has suffered or not but it still seems to function to expectation. Having said that, I have another Orion XS that I will install to "feed" it and to replace an ailing isolator.
 
One significant issue I do see with putting a FLA and a LFP battery simply in parallel is the disparity in voltages. Not so much charging-wise I think, because both can be charged at similar voltages as mentioned above, but without charging and under load. Because the LFP will spend most of its charged life around 13.1 or 13.2V but that's well above where the FLA sits at rest even when fully charged. IOW, under load, if in parallel, the LFP will keep the FLA fully charged and all the energy will come at first from the LFP, until it's pretty low at which point the FLA will kick in. Now, in some circumstances that may be a good thing, like if the FLA is the starter battery for instance and you'd rather be sure you can still drive off. But if you'd rather draw equally from both that won't work well and you do need better control.

That Orion XS seems better than the earlier versions for sure, but dang, it's not cheap.
 
Shoredreamer said:
Adding to the info above:
I use, sell and have installed lots of Dakota Lithium and Deep Cycle Systems Lithium batteries at my shop. Both brands have top support and quality construction with proprietary BMS and cells. They also have built in heating and Bluetooth monitoring with reliable apps. They also have the ability to crank an engine in an emergency start scenario.

Find or make a space where you plan to mount the battery and check dimensions and go from there. Dakota makes a 135ah in a Group 24 size. Deep Cycle Systems has their super slim 120ah at only 2” thin. That battery is the most advanced drop in Lithium now with thermal resin and passive cooling, very similar in temperature management to hybrid battery systems in cars. 120Ah Slimline Deep Cycle LFP Battery - https://deepcyclesystems.us/products/12v-120ah-super-slim-deep-cycle-lfp-battery

You’re not gonna want to charge any LiFePo4 directly off an alternator. You’ll need to charge it via solar and/or DC to DC charging.
Click to expand...
While that battery looks awesome... I can't justify 1000$. Also could you explain more about why I can't charge off alternator? Could I use an inverter to a DC to DC charger?
 
^ F, You can't use an inverter and a DC-DC charger together, one is AC output, the other is DC input. But you can use an inverter and an AC charger together, or only a DC-DC charger; if you feed either setup from a battery.
Now, as to which of the 2 would be the more efficient way to go, I don't know as it does depend on the specific hardware, of course, but am leaning towards the DC-DC approach, the newer ones seem quite efficient.
 
OP, curiosity is getting the best of me: Why would you want to use an inverter to power a DC-DC charger?
 
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