4WD Electrical upgrade; lithium, inverter and new DCDC
Not too long ago we did a pretty significant lithium battery upgrade to the Reconn R2 Hybrid Camper trailer, going from 240aH of AGM’s to 340aH of lithium, a big solar charger and inverter, and we’ll be putting 600W of panels on the roof.
Not long after though, we decided to upgrade our 4WD electrical system too, and are finally getting rid of our 43kg 150aH secondary AGM battery that has powered our fridge, lights and other accessories for the last 5 years.
Why the lithium battery upgrade?
Weight and space savings
Our Bosch BAC12-150 AGM battery has been amazing, and we’ve had zero issues with it. It has run everything I’ve wanted to, never been too small that I’ve been worried about power and its nicely tucked away.
The one real problem that I’ve never been too happy about though, is its weight. Even though its forward of the rear axle, 43kg is a lot of payload, and I’ve been really trying to put our Isuzu Dmax on a diet. Even worse, is the passenger side of the vehicle on the rear is 150kg heavier, which is where the existing battery sits.
The new lithium battery will come in at just under 20kg, which is a pretty significant improvement.
It’s also quite a bit smaller, and won’t stick out like our AGM did, which is good for putting other heavy items up against the headboard, and storage in general.
The other major factor is that our AGM is coming up to 5 years old, which is the normal sort of lifespan you’d get, regardless of cycles. Yes, it might last a few more years, but it might not too, and with some big plans in the future we need a reliable power source.
I’d also rather do the upgrade at home where I have a full suite of tools, than trying to do it on the road, as accessing the space that the existing battery in is not much fun. Better to replace it while you are ready, than have it fail when you aren’t!
Additional capacity, and greater power draw
With our AGM, we can do about 2 full days with no solar charge going in before we are starting to look for power (under existing consumption rates).
That’s not bad, but not quite at the level I want it to be at, and with the intention to charge more electronics in the future, I wanted more capacity. If we pull up and don’t move for 3 days and its cloudy, I want to know I won’t be stressing about battery levels, as it takes away from the enjoyment of your travels.
The Lithium Battery Upgrade will give us about 2.5 times the storage, and allow for a much greater power draw, and allow us to run up to 150 amps from the battery (basically an induction cooktop running at nearly 2000W).
I like to kick back at camp and relax, and not worry about battery levels, and for the additional price the extra capacity will be hugely appreciated.
We’re making a DIY Lithium Battery
Yep, instead of buying off the shelf 12V Lithium Batteries, we opted to purchase lithium battery cells, and make our own. If you’ve not looked into this, there are a million tutorials online for how to do it, and despite not being a 12V guru, I was pretty confident that we could build one without too much trouble.
Of course, it helps when you have a good mate who’s done it before, and has been using custom made lithium batteries for some time, and who offers not only to order them, but to help charge and assemble them with you!
What Lithium Cells did we get?
We’ve proceeded with 4 prismatic lithium cells, at 3.2V each, and 230aH. Combine the four together, and you have 230aH, at 12.8V. We’ve also gone with a 150A Daly BMS (battery management system), along with the busbars and other bits and pieces to make it all work together.
Testing showed they came in at around 243 and then 246 amp hours, which is pretty impressive, and a lot more than we’ll ever need.
These came from a reputable seller on Alibaba, and are grade A cells, used by a significant number of people prior. You can purchase these from hundreds of sellers, but you really want the peace of mind that they are decent before you lay your hard earned down.
What charger, shunt and screen?
At the moment we have a Projecta IDC25, which does not have a lithium profile (and its also not taking solar input anymore). You can still charge a lithium battery with it, but its not the correct profile and really isn’t ideal.
I’ve just put an order in for a Renogy 50 amp DCDC and MPPT and a 500A shunt and display (Battery monitor). Ironically our Projecta Dual battery monitor screen is almost illegible too, and despite being able to use the BMS to monitor the battery, a shunt is a much better option.
We’ve also ordered a 2000W Renogy inverter, which will replace our 400W Enerdrive Inverter. I never thought we’d use anything bigger, but with the idea of being able to run an induction cooktop, and potentially some other gear I figured why not?!
Want to know if its worth going to an induction cooktop or sticking with gas? Check out Induction cooktop vs Gas.
What did we pay?
Like usual, we like to let you know that we paid full retail price for all of this.
The 230aH battery cells, cell balancer and Daly BMS were $910.81 delivered.
The 50A Renogy DCDC, Shunt/Monitor and 2000W Inverter were $721 (on a sale again)
Stephen from Hunter Auto Electrics helped wire it all up again (and remove the broken Projecta DCDC plus replace the auto resetting circuit breakers with fuses), for $800 including a heap of consumables.
Power for days
This will give us 570aH of lithium batteries between the car and camper trailer, and that’s enough to live off grid for a long time (essentially forever in terms of power). Couple it with 920W of fixed solar, and the option of blankets/portable panels we shouldn’t have any power issues any time soon.
With 320L of water on board we should be able to find some nice, remote places and hang out for weeks without having to go into town for anything! Exactly what we want, and we’ll be putting it to good use!