Battery charger

[mothercoder]

Still trying to wrap my head around this so hoping I can get some simple answers. For the time being I won’t be getting solar. Not enough funds to go around. I will be getting a 200ah battery (probably Renogy but I’m not sure).  I will not be charging it when I drive. So I’ll need to charge from my 2000watt Wen generator or shore power. I know I need a battery charger. I will eventually be getting a 12v refrigerator but I want to wait until I can get a dual zone. I’m trying to buy to with future needs in mind but with current budget. ​

To that end, I was going to get a 1000w PSW inverter. Is there a charger and inverter separately or as one unit UNDER $300 (combined) that you’d recommend? ​

 

[John61CT]

I will not be charging it when I drive.

Why ever not? That's the cheapest and easiest charge source if you're doing any significant driving.

To that end, I was going to get a 1000w PSW inverter. Is there a charger and inverter separately or as one unit UNDER $300 (combined) that you’d recommend?

The combined units in decent quality are a lot more than that.

Inverters really have nothing to do with charging. What makes you think you even need one?

There are many reasons to buy separate units for each function.

The primary factor for a charger is amps output. How many do you think you need?

If you don't know, how large is your current bank, and what chemistry / type?

Are you going to be running it off a genny or just overnight mains power?

 

[mothercoder]

This battery charger has been recommended to me. https://www.amazon.com/gp/product/B0042T4GIW/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1

 

[John61CT]

I would not go with a multi-bank charger unless I knew the internal workings, a KISS design is easier to work with.

And that is a tiny current output for the size of most House banks.

No recommendation is possible without determining the Amps that *your* setup requires. And the other clarifying questions I asked are also relevant, I'm not just being curious .

Also note a good charger usually will cost a fair bit more than the battery bank it's suited for, especially for those on a budget.

But your charger should still be in use after that first bank has been replaced, maybe a dozen times; one is permanent infrastructure (like your axle) while the other is a consumable (like tyres).

 

[mothercoder]

Why ever not? That's the cheapest and easiest charge source if you're doing any significant driving.

The combined units in decent quality are a lot more than that.

Inverters really have nothing to do with charging. What makes you think you even need one?

There are many reasons to buy separate units for each function.

The primary factor for a charger is amps output. How many do you think you need?

If you don't know, how large is your current bank, and what chemistry / type?

Are you going to be running it off a genny or just overnight mains power?

Why not charge while driving?  First, I do plan on staying in one place for longer than a couple of days.  My batteries will need to be charged while I'm camped.  Second, my batteries will be in the cargo trailer.  I am clearly having enough trouble wrapping my head around keeping them charged while camped so adding in how to run power from my tow vehicle to my batteries is just not going to happen.  

I understand that quality will cost a lot more than what I'm looking at.  However, I can make money materialize out of thin air.  Some of us are working on a limited budget.  I'm not going to blow my emergency fund to have a high quality electrical system.  I can upgrade later.  I'm looking for something that will work for now.  

Why would I not need an inverter?  I'm not always going to be running my generator in order to have power to the trailer's electrical.  At some point I will need to use the power from the battery for my electrical needs.  Not everything I have is 12v.  

I'm working on my amp output need.

 

[John61CT]

Yes you likely need multiple charge sources if solar alone is not sufficient.

Maybe add alternator charging to your to-do list for later, when you have the money and mental bandwidth. It might just take a heavy pair of cables and the Anderson connectors. But if you're only driving a few hundred miles a month, never mind.

If you really need to use the mains devices when the generator isn't running, then yes you need inverters.

Doing without any mains devices may well make your electrical system more affordable, especially if it eliminates the need for a gennie too.

_____
Once you learn what list of chargers will be a good match for your bank, look at eBay or CL for bargains. IMO better than paying for the same functionality more than once. You should get an ammeter anyway, and that will allow you to test it on the spot.

The clarifying questions I asked are relevant to determining your amps requirement, as well as other factors in charger selection.

 

[mothercoder]

My needs to start out are very basic: charge my phone, laptop and portable DVD player, sparing use of interior LED lights, 12v Endless Breeze fan if needed, charge my Dremel a couple times a week and eventually run my 12v fridge. Perhaps at some point I'll add some 12v items like a blanket or 12v roof fan but nothing major. Most of my lighting will be solar (Luci lights, solar bulbs and puck lights). If I calculated right, I doubt I will use more than 80 amps/day.

I likely won't be adding solar until next year so what I get now I will need to charge with a generator or the few times I anticipate having shore power.

 

[jimindenver]

Alternator charging for a trailer is a waste of money, time and effort. You will need a converter/charger like a RV uses, something like this. It will charge your battery as well as provide for the 12v needs when plugged into shore power or your generator.

https://www.rvpartsnation.com/rv-el...rogressive-dynamics-9245-rv-converter-45-amp/

This is just a example because I do not have time to Google all day. Another option would be a PowerMax adjustable voltage charger because with a generator you will not be charging long enough to worry about going into float.

There are less expensive auto chargers at the auto parts store but they are built for shore power and low amp output. You do not want to fry your battery but then again you do not want to have to run the generator all day either. Some will say 2/12/70 but the 70 amp setting is for starting cars and only used for short times. Left on it will over heat and shut off.

 

[John61CT]

Yes that PD unit has a great rep.

A good charger designed for deep cycling batteries (not garage style) will do everything you need that the ones designed for RVs (called "converters") do.

If your bank is FLA and only ~200AH like a pair of Deka GCs would provide for under $200, then to save money 20-25 amps would be enough, as long as you didn't plan to get a bigger bank or to move to AGM chemistry in the future.

This would allow you to get away with a smaller (cheaper) gennie. Make *sure* you don't buy a charger too big for your gennie to run, since you're not likely to be buying a more expensive model that allows you to "de-rate" output, i.e. turn down the amps.

_____
Note your immediate needs may seem small, but running a high-CFM fan for many hours uses a fair bit of power. And even the most efficient 12V compressor fridge puts you over into "medium sized" needs rather than small.

I would advise not going lower than a 200AH bank with a fridge in your future.

Nothing you mentioned requires buying an inverter, and using one where not required will waste power.

______
Without very regular access to overnight shore power, going without even a small solar kit will mean an early death of any reasonably priced/AH battery bank.

It just isn't practical to run a gennie the 4-6 hours needed to get the bank back to 100% Full, especially when only a few amps are accepted for all but the first hour or so.

 

[mothercoder]

Well then, I don't know what to do. Because I can't afford all the things you all are telling me to get. How are other folks doing it because I guarantee you that half the people I observe living in vans are not spending this kind of money on power. I know I'm not by myself in this. I've talked to many solo women nomads who are equally scratching their heads and trying to understand how to get things set up. And as a whole, we are a pretty smart group.

 

[John61CT]

Nothing to do with women's brains of course.

Start with what you know you need now, get the better quality when you're in a better financial position later.

If you can't afford a setup that will last 5+ years, then just accept you might be replacing it every 2-3, or maybe scam the places that have NQA guarantees on their batteries.

Some even make do with discarded batts, get a few months out of them and move on when truly dead.

Post your total budget and maybe we can help post sample shopping lists.

But it's just basic fact if you use 100AH per day, a 5A charge source will take 25 hours to refill the bank, no matter your knowledge level or bank account.

 

[John61CT]

The more specifically you define your **needs** as opposed to what you'd like, or might get in the future, the less you need extra "fudge factor" that costs more money.

Reducing consumption will always be cheaper than adding capacity.

Many people just recharge their screen devices at coffee shops or the public library.

Driving where it's cool takes gasoline but means less energy required to stay comfortable.

 

[mothercoder]

After a talk with my BIL, I'm going to do just that: get what I need now and add more later. I won't have a 12v fridge for a while so I won't need a big inverter. And I'm going to go solar instead of getting the generator. If I feel I need the generator later, then I'll buy one. I'll see how it works out and then adjust. I have to give up the idea that I'm going to have the perfect set up right out the gate.

 

[B and C]

Buy pieces that you can build on. Nothing worse than having to replace something with something else because it no longer fits your needs. You don't want to mix an old battery with a new one either.

 

[mothercoder]

Buy pieces that you can build on.  Nothing worse than having to replace something with something else because it no longer fits your needs.  You don't want to mix an old battery with a new one either.

I will try to do that as much as possible.  Batteries I will try to buy with future need in mind.  Too expensive to have to replace them.  Inverter...not such a big deal.  If all I'm doing is charging my devices and running a fan every once in a while, 400-500 watts should be fine for now.  What I'm trying NOT to do and what I have been doing is trying to build the perfect system out the gate.

 

[John61CT]

After a talk with my BIL, I'm going to do just that: get what I need now and add more later. I won't have a 12v fridge for a while so I won't need a big inverter. And I'm going to go solar instead of getting the generator. If I feel I need the generator later, then I'll buy one. I'll see how it works out and then adjust. I have to give up the idea that I'm going to have the perfect set up right out the gate.

That sounds like a good approach.

Note the whole point of a 12V fridge is, that is what makes an inverter unnecessary!

The only caution is that it is not a good idea to add new batteries later to an existing bank, so bite the bullet on the $200 Deka bank, the very high capacity relative to your daily usage (starting out) will act as a great buffer for cloudy days.

Even if you do abuse it to some degree, FLA is very resilient, and that is the cheapest true deep cycle option anyway.

As I said a 20-25A charger will get it recharged as fast as possible when you do get access to mains power.

People will try to tell you you "need" 200-400W of solar for a 200AH bank, but that's just an overly general rule of thumb, sure would be nice one day but start out with 100W see how you go, unlike batteries, you can always add more solar later.

The keys will be:

making sure you're consuming less energy each day than your sources total input

try to only rarely go below 50% SoC on the bank

and get it to 100% Full every other day if possible, at least once a week

and it should last many years. Obviously you don't want to invest $150+ on the most accurate battery monitor, but you do need some way to measure AH in and out.

This may be "good enough for now"
https://m.ebay.com/itm/DC-120V-100A...emaining-Capacity-AMP-Voltage-AH/182147916411
The shunt gets connected right at the bank, and wire the display somewhere you can keep an eye on it but won't bother you in the dark.

Actually using Anderson connectors for the shunt that meter can become "mobile" to measure the total AH contributed or consumed by any single device over time

Great for troubleshooting issues before you get to buy a cheap hand-held ammeter, recommended at some point.

 

[John61CT]

400-500 watts should be fine for now.  What I'm trying NOT to do and what I have been doing is trying to build the perfect system out the gate.

Not to nit pick, just clarifying units of measurement: Watts measure power flow (like Amps) at a particular instant.

For storage capacity or usage over time, you need to use watt-hours, or with 12V systems we usually stick to AH (wH ÷ 12)

400-500AH is way more storage than you need for your bank.

400-500W is likely more solar than you'll want to invest in to start with.

And don't use any load device that burns at that rate, unless it's just for a few minutes per day.

 

[John61CT]

And that meter will also show you exactly what the energy usage is per minute or per hour, so you get a pretty accurate energy budget put together as you acquire each new device going into your van.

 

[John61CT]

Sorry left out "the usage of each consumer device as you acquire it"

in case that wasn't clear.

 

[mothercoder]

Not to nit pick, just clarifying units of measurement: Watts measure power flow (like Amps) at a particular instant.

For storage capacity or usage over time, you need to use watt-hours, or with 12V systems we usually stick to AH (wH ÷ 12)

400-500AH is way more storage than you need for your bank.

400-500W is likely more solar than you'll want to invest in to start with.

And don't use any load device that burns at that rate, unless it's just for a few minutes per day.

I was talking about the inverter, not the solar or batteries.  

BTW, I can't find the Duracell (Deka) batteries you were talking about on BatteriesPlus.