TL;DR - My Northstar 24F batteries have been great, but after 5 years, they are both dying. I need to start figuring out what I'm going to do next.
No green lights, no bueno.
The last few times I've picked up the Tacoma from storage - where it usually sits for 2-4 weeks without being started - turning the key has resulted in a very slow crank. Not only that, but even on trips - after charging on the alternator for much of the day as we drive around - the batteries just don't seem to provide that quick-get-up-and-go-juice that they used to
In fact, on days where we're out hiking, I've taken to setting up the solar panels in order to push every last ounce of electrons into the batteries, or at least keep them topped off while the fridge is cycling more frequently during the warmer daylight hours.
I must admit, I do like setting up the solar, even if it doesn't provide that much power and will never pay for itself (by a long shot).
The easiest thing would be to simply replace the existing AGM batteries with equivalent power sources, but battery technology has improved in amazing ways over the last five years, so right now I'm leaning towards an entirely new system.
My idea - at least, until I learn more - is to:
- Replace the starting AGM with another AGM. Likely, I'd go for something smaller and lighter than the 24F, and I'd consider mounting it in the cab in order to remove weight and clutter from the engine bay.
- Replace the house AGM with a LiFePo house battery. I'm thinking I'd go for something way overkill in the 200-300Ah range, and then I'd also need a DC-DC charger and a few other bits that come with running what would essentially be a second electrical system in the Tacoma.
There are a couple "problems" - or perhaps just differences/things I need to learn about - with this setup compared to the two-AGM-solution I'm currently running:
- Since I can't link the AGM and LiFePo batteries, I'm not sure how to use the solar panel to charge both batteries when I'm out on a hike all day. Or, really, even how to use the solar to charge both battery "banks," since the MPPT controller will have to be hooked to one of the banks.
- I'm not 100% confident in my ability to jump start myself - or somehow recover - if the new, smaller AGM starting battery goes dead. Today, with the Blue Sea ML-ACR, I can just link up the house battery and give myself an instant jump.
I've got a couple months before the Tacoma comes home, so I'll be keeping my fingers crossed that the Northstars last a few more trips - and figuring out what to replace them with - in that time. Suggestions welcome!
In this Series
the nice thing with a LiFePo battery is getting a bluetooth BMS to tell you state of charge, input/output, etc. I put a cheap Vatrer one in my travel trailer and I love it.
I just put an AGM battery in my tacoma. costco is carrying AGM again and they are only a little more than SLA. I haven't had my truck tweaked to put out how voltage for them. how long are they lasting for you in the desert heat?
there are only a handful of people making LiFePo starting batteries (Dakota and AntiGravity I think. ). And not too many success stories (just one overlander I found a video of that loved their AntiGravity). The AntiGravity does have a nice feature to 'jumpstart' that might even let you get away with just one battery if your power needs are not that much.
Yeah, I don't think I'm ready to commit to a LiFePo starting battery yet, since it's not uncommon for me to be out and about when it's below freezing, but I feel like it'd be dumb to ignore the more modern tech for the house battery. Plus, it's always fun to build out a new system and learn the way things work.
Monitoring will be nice for my nerdiness. I do love the monitoring that the Victron MPPT Solar Charge Controller gives me, even for the current setup with AGM batteries.
Thanks for the tip on Costco, I'll definitely check that out. I've also had good luck at Batteries+, which use Northstar as the manufacturer for their house brand of X2Power batteries. 👍
I am running an optima 24F on the starting battery, and I have a SOK 12V100AH LIPO4 for the house battery for lights and refrigerator. I was running 2 100 watt Renogy flexible panels on the roof of the ORU camper, and this morning I added 2 more for 400 watts. I am considering going up to the SOK 206AH battery. Same basic footprint, just taller. I have the Victron chargers, the 18 amp DC-DC from the alternator, a 15 amp AC charger, and I just swapped from the 75/15 MPPT charger to the 150/45 MPPT charger to handle the new panels. This power system has been running very well. The SOK battery has the built in heater. If I run down the starter battery, I have one of the capacitor jump boxes. It has worked well when I have had to use to start my Camry after it sits for long periods. It can be charged from the dead battery, or I can charge it from the LIPO4 battery. I agree, I am not sold yet on lithium for the starter battery. I am also running the Victron chargers and Renogy batteries and panels on the travel trailer, and they have been working well.
Nice, sounds like you've got a great system setup there Larry! Lots of solar for you, too. I've only got a single 100W panel, but so far that's been all I need to keep the fridge running and devices charged on days when I'm not mobile. Of course, I've been lucky that most of those days have been sunny; I'd probably need more panels if I had to account for overcast days, etc.