BLITZEN goes Lithium

[Trail Talk]

After much consideration, including playing around with cardboard mock-ups, we had to face the fact that installing a 3000w inverter/charger would cost us a cabinet. We weren’t ready to accept the loss of valuable storage space for something only “nice to have”. Instead, we asked OEV to upgrade our solar panels. The newer bifacial designs offered a 30% gain within virtually the same footprint!


Heading out in a couple of days for some off-grid adventures and looking forward to seeing the results. We have room for at least a couple panels more but I’m not yet ready to give up the carrying space.

 

[calameda]

we asked OEV to upgrade our solar panels. The newer bifacial designs offered a 30% gain within virtually the same footprint!

been considering this myself. What panels did you opt for?

 

[DiploStrat]

Aside from all the well-known advantages of converting to Lithium batteries, we did lose a bit of functionality :-(

Due to the incompatibility of our LiFePO4 house batteries and the lead-acid truck batteries (the same reason we needed a DC to DC charger) our Samlex dual-sensing voltage relay became redundant.

The Samlex would allow shore power to first charge the house batteries, then the truck batteries. It further prevented either from draining the other side. Now our dual truck batteries are removed from the charging mix.

Not sure yet if that will prove a disadvantage during freezing weather, but "experts" say that a fully charged battery is the best protection vs battery warmers.

Has anyone found a means of retaining the truck battery charging from shore power while using lithium in their house?

Yes, the "Twisted Sister™" set up with two B2B. (Given to me by REDARC.)

Basically:
-- One B2B charges from the starter battery to the camper battery, with an added relay to assure that it only does this with the ignition on. In our case, this takes from 24v lead acid and outputs 12v with a lithium iron profile.

-- A second B2B (can be smaller) charges from the camper battery to the starter battery, with a relay that assures that this B2B is disconnected when the engine is running. (Easy to do with a "crossover" relay - basically, when the ignition is on, the relay is on, but this disconnects the power.) In our case, this takes from 12v lithium iron and outputs 24 lead acid.

Worked like a charm for over five years. Never bothered to add any kind of cut out. You could, as this second B2B is really only needed when the truck is in storage.

 

[Trail Talk]

been considering this myself. What panels did you opt for?

Lumera, made in BC. Our 170w panels were replaced with 220w, requiring new mounting brackets but nothing else.

 

[Trail Talk]

Yes, the "Twisted Sister™" set up with two B2B. (Given to me by REDARC.)

Basically:
-- One B2B charges from the starter battery to the camper battery, with an added relay to assure that it only does this with the ignition on. In our case, this takes from 24v lead acid and out puts 12v lithium iron profile.

-- A second B2B (can be smaller) charges from the camper batter to the starter battery, with a relay that assures that this B2B is disconnected when the engine is running. (Easy to do with a "crossover" relay - basically, when the ignition is on, the relay is on, but this disconnects the power.) In our case, this takes from 12v lithium iron and outputs 24 lead acid.

Worked like a charm for over five years. Never bothered to add any kind of cut out. You could, as this second B2B is really only needed when the truck is in storage.

Thanks for confirming this. We left the Samlex cable in place in anticipation of doing just that but I have to get on with it

 

[DiploStrat]

Thanks for confirming this. We left the Samlex cable in place in anticipation of doing just that but I have to get on with it

There used to be a really neat product, designed especially for this purpose, the AMP-L-Start, but they appear to have gone out of business. Pity as it was small, neat, and even had a lithium to lead acid setting.

Adding a second B2B is pricy, but you may be able to find a small one.

 

[Trail Talk]

Adding a second B2B is pricy, but you may be able to find a small one.

I discussed a second charger more in-depth with the good folks at OEV while there for the solar panel upgrade. We came to the conclusion that the best way forward was to repurpose our existing Orion 12/12-30 DC to DC for the camper to truck circuit and install the newer Orion XS 12/12-50 for the truck to camper circuit. Lot of advantages with that new Orion XS, will be on our to-do list for 2025.