batteries bank, inverter and charger for my chevy

Re: batteries bank, inverter and charger for my chevy

Here is where rules of thumbs meets the road...

First, what are your real loads and operation conditions going to be like?

Will you be operating for 24 hours on battery, or will it be more of a mix of 2 hours on battery, drive an hour, another 3 hours on battery, etc. (such as a traveling large animal vet).

Next, why are you looking for battery usage? Many times, a small Honda eu1000i (900 watt) or eu200i (1,600 watt max) class generator will be very cost effective. You can get 4-~10 hours of run time per gallon of fuel, they are quiet and small (easy to move from van to a work site), and can run 2,000 to 6,000 hours with good maintenance (i.e., oil changes per manual, good fuel, etc.).

And for portable applications, some times the 50% maximum discharge rule of thumb is not practical. For example, good batteries will support an 80% discharge, just with fewer cycles (maybe 500 deep discharge cycles vs 1,500-2,000 shallower cycles). But if your battery volume/weight is almost 1/2--Then that may be a reasonable trade off.

Also--AGM vs Flooded cell... AGM's can have very high surge current ratings... If you need to start a pump etc. for a short period of time, AGM's can support those very high currents--Where it would take a much more massive flooded cell bank to have similar power delivery characteristics.

If you are concerned about costs, then flooded cell golf cart batteries are some of the best deals out there (new). They are cheap because they are used in high volume. They are a bit messy (like all flooded cell batteries), forgiving if over charged (you can add water, can't do that with AGM), and good "training batteries". Pretty much everyone here has either damaged their first set or two of batteries (poor maintenance, over/under charging, loads left on for a few days, guests plugged in hair driers-turned on all the lights-took long showers--and killed the battery bank). Also, if you don't know what you really need--You can get the minimum amount of "golf cart" class batteries and run them for a few months to a couple years--Then replace them with better/bigger/smaller/different batteries have you have learned more about your needs.

To a degree--You can even do this with a generator for a few weeks/months... Just get a Kill-a-Watt class meter (some have batteries for backup memory, others reset back to zero when AC power is removed) and log your usage (by session, by day, etc.--What ever makes sense) and get a detailed usage of your real power. Then design the battery bank/charging resources need to meet those needs (and the genset still may be your backup power source anyway--so it is not a waste of money either).

There are a hundred different ways of addressing your needs. Some may be more cost effective, others may be more reliable, and others yet may not fit in your vehicle--so won't work anyway.

There are the "different" chemistry batteries out there too--NiCad (still used a lot in aviation), and the upstart Lithium Iron Phosphate Batteries; LFP; LiFePO4 (expensive, lightweight, very interesting features--but you need to know what you are doing).

The end result is a 50% cycling 450 AH 12 volt golf cart battery bank is going to weigh around 268 lbs (plus weight/space for inverter, charge controller, wiring, etc.) and run your loads for ~1-2 days before recharging. A Honda eu2000i (1,600 watt) generator is going to weigh around 50 lbs and run your loads on ~1 gallon of gas per day (or a bit less).

There are other things you can do too... You can run off the battery bank for smaller loads/quiet time, and the generator for heavier loads and/or when the genset will not cause issues with your usage (fumes, noise, etc.).

Again, I am not trying to say I have all the answers (obviously, I do not)--But I really still am not sure I understand your needs to where I can even give you a better answer (I may have missed some important parts--Like will you be able to recharge "back at home" (or at a camp ground, etc.) from utility power at the end of the day.

You are not camping (I think)... This sounds more like a work related vehicle or remote education, etc. type application--So what happens "at the end of the day"?

-Bill