AGM or Lithium

[outinthewoods]

Hi all -
I have a new-to-me 2005 Hawk. I am embarking on learning about and hooking up my electrical system for the first time and am looking for some advice.

I am trying to buy a battery just once, but it may depend on a few things.

Here's the current setup:
1 - CAMPER DOES NOT HAVE A BATTERY CURRENTLY
2 - no solar
3 - Basic lighting setup
4 - Iota IDP-30 distribution panel
5 - Iota DLS-30 (non IQ4)
6 - 3-way refrigerator that doesn't work. Will upgrade soon.
7 - Furnace
8 - Maxx fan x 1
9 - Electrical system never connected and tested (by me), so I don't know if things are working correctly.

First off I'd better say that I'm very green when it comes to understanding electricity. Very.

In 6 months or so I have plans to redo the cabinetry and get the camper more up to snuff for a lithium powered system with all the new electronic gear and with solar, but for now I was wondering if I can install just a lithium battery with the gear that I currently have instead of buying an AGM and then in that 6 months having to sell it off and then buy a lithium battery.

Considering my current setup, can I do that and expect the battery to last or even charge?? My current use is about 2 trips/month, each one 2-5 days long. Future trips probably a week long or more.

I'm aware of the pros and cons of AGM vs Lithium, and eventually I'm going to go lithium as stated. I have read the manifesto but did not see information about whether or not I could run a lithium battery on what I currently have, while I'm waiting for about 6 months to do all the remodeling and rewiring, etc.


And what brands should I be looking at? For AGM if I have to go that way, or for lithium.
Thanks for your help!

Jason

 

[ckent323]

Figure out your power needs first. Think about where you camp, what seasons and what devices you plan to use. Do your best to estimate the power consumption (folks here can probably help).

Here is a link to the amps per day spreadsheet.

Amps Per Day Spreadsheet

Star 152 came up with this spreadsheet to calculate amp use per day. Pretty cool! The file uses default values for his camper - update as needed. Amps Per Day Spreadsheet

www.wanderthewest.com

Once you know that you can select a battery size and also a solar panel size.

I am an AGM owner and user but if I were installing a system now I would think hard about going with Lithium Ion.

Since you do not have solar I would suggest a lithium ion battery. My guess is that a good quality Lithium Ion battery of 100Ah will be sufficient but you should do a little research to be sure.

AGM batteries should be fully recharged after every discharge (every day during use) and should not be discharged below 50%. Lithium Ion batteries are not degraded by having a partial charge without fully recharging and can be routinely discharged to 10% or so.

I recommend going with a battery brand that is well regarded since they are not cheap. Brands with a good Battery Management System (BMS) and good build quality such as Battleborn and Renogy should be considered even if their prices are a bit higher. If you are competent with battery technology and battery management systems then perhaps you can sort out if cheaper brands are worth the money.


I hope this is helpful,

Craig

 

[PaulT]

Check the DLS-30 end with the fan. Look for a socket that can take a telephone cable. That is where you plug in a IQ4 control module. You pick one required for the battery type; e.g., IQ4-LIFEPO for a LiFePO4 battery or IQ4-AGM for a AGM lead-acid battery.

Best thing may be that cost is reasonable so that you could start with one for lead acid & switch to another for LiFePO4 later or vice versa.

Take your time & explore your options.

 

[buckland]

I think adding the a IQ4 control module, (real cheap on line) which will allow you to charge a Lithium battery with shore power is good advice. I am in favor of getting a good LiFePo4 100 ah (Battleborn etc) and building out from there. An Isotherm refridge (2 way AC/DC) runs on very little and is super quiet.
Our very own Dr Electric will be, I'm sure, helping out with learned advice.
Welcome to the best darned forum on the planet...tons of experienced builders of camper platforms.

 

[FAW3]

Determine your individual needs, plan your project out, then build it once, right.

We are boondockers and rarely use shore power, often just at home the day before or after a trip to power the Isotherm 12/120vt refrigerator and/or to power a portable electric heater to maintain temp for the water system. The shore power system is not designed for Li-ion, but I did not upgrade as we so rarely us it. It charges the Li-ion battery "good enough" with the solar system being the primary.

Our primary battery charging needs are met with solar and the FWC standard truck alternator charging system. The solar controller, a Zamp 30, is set to Li-ion. We have one 100ah Renology Lithium battery. We have one one fixed 160 watt solar panel on the Hawk, and a Bluetti PV120 portable panel with extension cord for the rear FWC solar port. Having the fixed panel is nice and simple, but for shady spots, low sun angles the portable panel is great to have and use when needed.

The nearly flat discharge voltage profile (helps furnace, refridges to run properly), low weight, no off gassing, and ability to use the full capacity of a LI-Ion battery are the huge benefits of the type. You want a battery with an internal Battery Monitoring System (BMS) and a Bluetooth phone app for battery monitoring.

How much battery? I transitioned from two AGM's to one Li-ion 100ah, figuring I'd likely have to add another. Nope, the single 100ah has worked for us just fine.

As far a brands...I forgo the top and the bottom brands...and typically run the upper middle of the line.

Tripping around with this set-up..."battery power" is not something I think about routinely. That's the real destination you are aiming for.

 

[Wandering Sagebrush]

Congrats on the new to you camper, and welcome to WTW!

I am still an AGM guy, but if I had a blank slate and need/opportunity to go to LiFePo4, I certainly would. The folks who posted above have great advice. I hope you’ll document and post your build and conversion. Have fun!

 

[rando]

Yes, you can just install a lithium battery with the gear you have.

In this day and age I cannot see any compelling reason to use a lead-acid battery. For LiFePO4, it seems that 100Ah is the sweet spot for most folks who also have solar (me included). The normal Iota DLS-30 is not 100% ideal for use with Lithium, but will work fine, particularly if you have solar to give it a boost charge for balancing every now and then.

As for brand - I would also recommend a 'middle of the road' brand like Renogy. I don't see any good reason to pay twice as much for a 'premium' brand - they don't offer any extra capabilities or features and even if the battery only ends up lasting 25% of the advertised cycle life, that is still way more than you would ever need. But also realize that lithium batteries store a boat load of energy, so you would want to stick with a company with some sort of track record, so avoid the bargains on EBay and Amazon.

 

[CPT Davenport]

Determine your individual needs, plan your project out, then build it once, right.


Our primary battery charging needs are met with solar and the FWC standard truck alternator charging system.

I have always wondered about doing this, but when I ask this question everyone says don't do it for a variety of reasons. It is nice to hear from someone who actually is using stock alternator charging with lithium! I disconnected mine and rely on solar only. Most folks say to get the DC-DC charger for lithium but that requires a wire upgrade. I will also charge my lithium with the FWC stock charger from shore power. This does not get me to 100% SOC but very close. My thought has always been to hook back up my alternator charging wire, not to completely charge, but to get me through on cloudy days and over the hump.

 

[rando]

I have always wondered about doing this, but when I ask this question everyone says don't do it for a variety of reasons. It is nice to hear from someone who actually is using stock alternator charging with lithium! I disconnected mine and rely on solar only. Most folks say to get the DC-DC charger for lithium but that requires a wire upgrade. I will also charge my lithium with the FWC stock charger from shore power. This does not get me to 100% SOC but very close. My thought has always been to hook back up my alternator charging wire, not to completely charge, but to get me through on cloudy days and over the hump.

I have done it both ways - I started by just using the stock Blue Seas ACR between the truck and camper and then switched to using a DC-DC charger. It works OK with just a wire (mine is 8 AWG, but that probably doesn't matter), but with a Tacoma with a smart alternator the voltage quickly drops and the charge rate is low - like 3-5A. So it is something, but probably not enough to recharge your battery significantly.

I now use a DC-DC charger, it is 30A max, but I usually set it to charge at 20A. You don't necessarily need to upgrade your wire for a DC-DC charger. The whole point of them is to boost and control the voltage from the alternator right at the camper battery. The DC-DC charger will compensate for the voltage loss in skinnier wires from the truck to the camper. There are two caveats to this - the wire ampacity needs to be high enough for the anticipated current draw and you may have issues with 'engine running detection' as the voltage drop in the wires can trick the DC-DC to think the engine has stopped. For 12AWG the ampacity is 25 or 30A depending on the insulation rating, so the stock wire can accommodate a 20A DC-DC charger. Victron has some smart methods for engine running detection - either using the stock wiring and pausing charging to see what the true voltage is, or you can run a separate 'engine on' signal wire to turn the DC-DC charger on when the engine starts.

We typically use about 30Ah in 24 hours and rely on solar for all our charging, but we will get back to full in about 2 hours of driving if it comes to that.

 

[FAW3]

Outinthewoods, you might also check YouTube for FWC content about your camper and it's various systems...the FWC videos are a great resource.

There is "typically" an umbilical cord that connects to your vehicle. Back in the day it would involve a wire circuit that tapped from your truck battery, have a fuse, then run to a simple connector. The connector matched up to the truck umbilical and went to a "battery separator" to ensure camper draw did not deplete your starting battery. It would charge the camper battery from your truck when running. For wider campers like a Hawk, it also provided a power source for your camper running lights.

 

[pods8]

With the prices of mid tier lithium batteries coming down to a AGM pricing I see hardly any scenarios I'd use an AGM still.

Bang for the buck with build quality still I'd strongly recommend powerurus, they are built by roypow and if you watch a tear down video they are assembled well with good components. They have low temp protection and bluetooth as a standard so you can monitor what your batteries are doing.

Lots of folks will recommend chins, litime, etc. to save a couple bucks but frankly the powerurus in my research is just build a little better for marginal cost difference.

 

[Jon R]

Another good company making USA-assembled batteries with all new prismatic Chinese cells is bigbattery.com. I like that it has a stainless steel case, a recessed SB175 connector, an on/off switch, and large voltage display. My 200 ah battery from them is going strong and will be four years old this Spring. There is a Will Prowse teardown video of this battery. It’s quite a bit less cost than Battleborn, but more than the overseas assembled batteries. Here’s a pic of mine in my Grandby’s battery compartment.

 

[pods8]

Another good company making USA-assembled batteries with all new prismatic Chinese cells is bigbattery.com. I like that it has a stainless steel case, a recessed SB175 connector, an on/off switch, and large voltage display. My 200 ah battery from them is going strong and will be four years old this Spring. There is a Will Prowse teardown video of this battery. It’s quite a bit less cost than Battleborn, but more than the overseas assembled batteries. Here’s a pic of mine in my Grandby’s battery compartment.

Doesn't look like they make it anymore, just an expensive 400ah with a different feature set, unless I missed it in their site somewhere.

 

[Jon R]

Doesn't look like they make it anymore, just an expensive 400ah with a different feature set, unless I missed it in their site somewhere.

I see that. Google still finds the page for my battery but it isn’t linked on their active site, so maybe it’s discontinued. I’ll call and ask them when they open.

Update: i called and pods8 is correct. This company does not currently offer any 12 v battery smaller than 400 ah.

 

[kmcintyre]

As others have stated, you'll need to figure out what the size of battery you need. Just do the LifePO4. So many reasons; all covered above and in other forums). I built my own. Purchased cells and BMS via China (most cells come from there anyway but it does take time). Pretty easy to do but you'll want to make sure your wiring from the alternator goes through a DC-to-DC charger, has thick guage wiring, fuses, etc., etc. Still not difficult in general. Purchasing a battery from above mentioned companies is a good idea too but you'll still need the other components. If you want to go down a 'rabbit hole' check out Will Prouse's videos.