We will try to lead ourselves through a modern energy journey of Solar charging, Lithium Iron Phosphate batteries and the rapidly changing products/resources available to power our hobby, RV, Campsite, Picnic, vehicle and even our homes. Hang on, this can be quite a ride!
We can start with types of batteries 18650 cells, Simple 3.2 volt single cells that can be assembled into many different voltages, physical configurations to fit nearly any space you have available or into containers available or shrink wrapped into your personal designs, You likely have seen commercially available “packs” of these from vendors like Bioenno battery or their competitors. the pre-built batteries typically contain a BMS (Battery Management System) that includes charge control, temperature sensor and automatic “Balance”.
There are many different battery (cell) suppliers, Some reputable many not so much, usually you have no recourse on used (reclaimed) cells, you need to test each cell and find a recycler for the ones you decide to discard. There are many ways of assembling these cells, prewired holders 18650 battery holder – Buy 18650 battery holder with free shipping | Banggood.com, 18650 cell holders that can be assembled into different configurations but have no electrical connection.
To electrically connect the battery some diy builders solder the these cells, which most believe is a very bad and dangerous idea but most use nickle strip and use a special “Spot welder” designed for this purpose.
You will need some version of a BMS, there are many styles, types, flavors available and it may take some research to conclude which will serve your needs.
There seems to be a endless number of “battery Builds” on YouTube using these 18650 cells and some of their slightly bigger brothers a quick search using the “18650 build” or “Powerwall build” will list lots of videos, choose carefully, as with all YouTube offerings there are good, bad and terrible videos many claiming theirs is the “Best on YouTube…
The Big Power Options:
There are larger “Prismatic” cells with much greater capacities, these still require a “BMS” and have some special containment needs.
The prismatic cells have been dropping dramatically in price, there are new and slightly used options. The competition is great and there a many different suppliers but there are some very reputable YouTube “influencers” that review the latest offers from both cell providers and battery manufacturers. I follow a couple of these YouTubers and really enjoy most of their content. I operate a solar charge/storage system in my motorhome and in the past powered our families off-grid cabins on solar power. Watching some of the changes and improvements in battery technology and Solar power generation.
My favorite solar power YouTube guru is Will Prowse of Mobile Solar Power: Made Easy! DIY Off-grid Solar Power! (mobile-solarpower.com) has developed in income, and bought his way out of homelessness by sharing his experience with mobile solar power while living in a motorhome.
Another is DavidPoz he shares his experiences of off-grid power and being “Energy frugal” by building some of his own batteries and solar array for his home.
Below is an example of a “Prismatic” LifePO4 battery, four 3.2 volt cells just add three buss bars to series connect them and a BMS (Battery Management System) ie. a Daly 12 volt 250 amp 4s Amazon.com: DALY BMS 4S 12V 250A LiFePO4 Battery Protection Module PCB Protection Board with Balance Leads Wires Protect BMS 18650 Battery Pack 12V Common Port with Cooling Fan: Electronics.
These cells are readily available from 100 amp hour to 300 amp hour, if you do some quick math at 700+ dollar for the 280 AH cell pack even adding the BMS with upwards of 3500 charge cycle compared to 300 cycles for a deep cycle Flooded Lead acid batteries, lets use Trojans 265 AH 6 volt X 2 @ $524 for the pair. That should easily be enough to convince you! it’s convinced me, time to swap my motorhome house batteries for the lighter longer lasting options.