LFI: Charging For Dummies

[Headache]

Sorry I can't be more help.

You're first 2 posts covered that.  I didn't know how to convert a number like "60,000 mAh" into something more understandable to me.

If you don't mind, would you please show me how to figure out approximately how long I could use something like what I linked in my first post to charge my craptop and phone also listed in my first post?  I'm not sure I'm asking the question properly but it's how the words formed in my head.  Frustrating day. I'm asking because it looks like what I may end up with unless I find better or a relevant alternative gets posted.

 

[Gunny]

https://www.harborfreight.com/3-in-1-portable-power-pack-with-jump-starter-62306.html

Would something like this work?

Rob

 

[user 37446]

I can only offer one suggestion here.  I read a blog once where somebody had a backpack with a power strip in it to which she had the power supplies for her phone, laptop, etc. plugged in.  She would go into the public library and set the bag down next to an outlet and plug the single cord from the powerstrip into it.  Done right, she only needed a couple of inches sticking out.  She would then sit there and read books or magazines while her stuff recharged.  Nobody ever said anything to her.  Probably didn't even notice, or if they did, they just didn't care.

Sorry I can't be more help.

That's exactly what I would do. A household (indoor) rated extension cord, 10' (reaches far away plugs) with 2-3 spots to plug into. Just dont get the ones with grounding holes...

It's hard to sit in the same area for hours on end but you'd be surprised how much recharging you can get from library or coffeeshop ac plugs in just an hour or two...

 

[user 37446]

That's exactly what I would do. A household (indoor) rated extension cord, 10' (reaches far away plugs) with 2-3 spots to plug into. Just dont get the ones with grounding holes...

It's hard to sit in the same area for hours on end but you'd be surprised how much recharging you can get from library or coffeeshop ac plugs in just an hour or two...

Oops, I meant "don't get the ones withOUT grounding holes".  The cheapo extension cords at Walmart dont have the 3rd hole. If you get one of those you will need the 3 to 2 adapter. It's better just to get a power strip that can accommodate multiple plugs and 3 holes each.

 

[Optimistic Paranoid]

If you don't mind, would you please show me how to figure out approximately how long I could use something like what I linked in my first post to charge my craptop and phone also listed in my first post?  I'm not sure I'm asking the question properly but it's how the words formed in my head.  Frustrating day.  I'm asking because it looks like what I may end up with unless I find better or a relevant alternative gets posted.

Sure.

First, a minor warning.  No inverter is 100% efficient.  There are always losses in the circuit, such that even though mathematics says it should drain X out of a battery, in the real world, it always drains X + a little more.  We won't know exactly how much that little more is, but we could guess that the inverter is about 90% efficient.  That's a rough rule of thumb.

Secondly, we decided that the device we talked about had about 48 useable amp hours.

Ok, you're going to have to look at the chargers for your phone and laptop for some numbers.  They're usually pretty small, so you may have to use a magnifying glass - I did.

The recharger for my Android tablet says:

Input/Entree:  100-240 V - 50-60 Hz 0.35 A
Output/Sortie:  5.0 V == 2.0 A

This is typical for USB charging devices and I would be surprised if the charger for your phone was very different.  This means it uses about a 1/3 of an amp every hour, so for every 3 hours you had it plugged in, it would drain 1 amp hour (mathematically)

I have a Lenovo laptop.  The charger for it says:

Input/Entree 100-240 V 2.5 A 50-60 Hz
Output/Sortie 20 V 8.5 A

So at full power - which it doesn't always run at, another complication - my laptop will use 2.5 amp hours every hour it's plugged in.  (again, mathematically)

So if we plugged both the laptop and the phone in for 6 hours a day, we'd use 6 x 2.5 = 15 + 2 = 17.  Say 20 amp hours, allowing a fudge factor for the inverter inefficiency.

I should mention that my laptop is fairly high end - I needed it for doing Photoshop - and it's probable that your laptop charger uses less.

You also mentioned some lights.  If you can find some numbers, I can maybe help with that.  LEDs don't draw much at all, incandescent bulbs draw a lot.

One thing you didn't mention was whether you'd be sitting full time, or driving every day, or whatever in between.

You could get one of those little USB charging dohickeys to plug into your cigarette lighter, and it might be possible to find a 12 volt car charger for your laptop.  If so, you could do much of your charging while driving.

 

[Optimistic Paranoid]

https://www.harborfreight.com/3-in-1-portable-power-pack-with-jump-starter-62306.html

Would something like this work?

Rob

Lead Acid battery, not lithium, so the 50% rule would apply to it, and only 17 AH, so less than 10 usable AHs.

 

[Headache]

https://www.harborfreight.com/3-in-1-portable-power-pack-with-jump-starter-62306.html

Would something like this work?

Rob

I'm not sure.  It doesn't have house receptacles on it which I do need for a couple of things.  I looked at this one but it doesn't have them either:

https://www.harborfreight.com/5-in-1-Portable-Power-Pack-with-Jump-Start-62747.html

TBH I keep going back to the PowerOak: https://www.amazon.com/gp/product/B017WCOKGI/

It has all the plug ins I need, charges in 5 hours off a 120w solar panel(future purchase)and faster if you use more, and they claim 35.2 amp hours.  It's a lot of money but if I'm going to be stuck here for a couple of years I might as well make it as enjoyable as possible.  I can get a lot of studying done if my craptop is charged.

 

[Optimistic Paranoid]

Note that the Ah rating of a power pack may be at 3.6v, so much less power than at 12v.  Any power pack that is advertised as a generator is at best misleading.

That comment worried me a bit, since I have zero experience with lithium ion and I know you run that for your house batteries.

I'm also troubled by the fact that I can't find a home web site for the company that makes this.  I was hoping to find an optional adapter wire for their 12 volt ports.

Looking over the 5 reviews posted on Amazon, I see one said he ran his desktop computer and modem for 7.5 hours with one, and another reported he used it to power a Cpap overnight with only a 20% discharge.

These make me hopeful that there's some real power stored in this.

 

[Headache]

So if we plugged both the laptop and the phone in for 6 hours a day, we'd use 6 x 2.5 = 15 + 2 = 17.  Say 20 amp hours, allowing a fudge factor for the inverter inefficiency.

I should mention that my laptop is fairly high end

You also mentioned some lights.  If you can find some numbers, I can maybe help with that.  LEDs don't draw much at all, incandescent bulbs draw a lot.

One thing you didn't mention was whether you'd be sitting full time, or driving every day, or whatever in between.

You could get one of those little USB charging dohickeys to plug into your cigarette lighter, and it might be possible to find a 12 volt car charger for your laptop.  If so, you could do much of your charging while driving.

My laptop isn't anything remotely high end and struggles with the latest Warcraft expansion.  Some of my classes(web development) are a test of patience.  If I knew how to rebuild this into something better(I build all my pcs) I'd be buying the parts.  That being said, I make it work hard and on a typical day in the house can be on it for over 10 hours.  That time has been significantly reduced since I started van living but now that I'm "stuck" I need something to keep my mind busy.

As far as lights I don't know what yet but whatever they are they will be LEDs.  I do have an LED lamp I really like and even have room for.  IIRC it uses 1.2 amps?  I had to email them and ask but it's in storage so I'll have to find something else to use for now.  This is the one I have:

https://www.amazon.com/gp/product/B0052OTB6S/

I'm open to suggestions for lights.  One nice thing is with the headliner gone I can use magnets and stick lights up without making it a permanent installation.

With my transmission and rear end needing replaced I'm limiting myself to driving once or twice a week and very close by so not enough to recharge electronics from, and as I've mentioned several times the cig plug doesn't work and won't be anytime soon.  That's why I'm shopping.

 

[Optimistic Paranoid]

I took a look at this light on Amazon.  Drilling down through the questions, found one where somebody needed to buy a new AC to DC wall wart for it.  They provided the specs.

Input: 100-240 V 50 -60 Hz 150 mA
Output:  5.0 V 800 mA

150 mA is .15 Amps, so this light uses even less power than your cell phone charger.  Good choice.

 

[Optimistic Paranoid]

I didn't know how to convert a number like "60,000 mAh" into something more understandable to me.

I probably shouldn't tell you this, since it makes me look much less genius-like   but I just use Google for stuff like that.

Type in something like "convert mm to in" or "convert mA to amps" and a little widget pops up that lets you type in the known number directly and automagically gives you the answer.

 

[Headache]

I took a look at this light on Amazon.  Drilling down through the questions, found one where somebody needed to buy a new AC to DC wall wart for it.  They provided the specs.

Input: 100-240 V 50 -60 Hz 150 mA
Output:  5.0 V 800 mA

150 mA is .15 Amps, so this light uses even less power than your cell phone charger.  Good choice.

Do you have a link?  What's a wall wart?

 

[Headache]

Type in something like "convert mm to in" or "convert mA to amps"

That's the magical part.  I wouldn't have known to type that or that it needed a conversion.  That's how little I know.  I am pretty confident in what I need but not how to get there.

 

[John61CT]

60,000mAH = 60 thousand milli amp-hours.

milli = 1/1000

so 60AH

but if that is at 3.6V, and you pull 19V for your laptop, it works out to <15AH


Do NOT put an inverter in the mix, that adds to the weight and complexity and is inefficient.

Your battery is DC, your devices charge off DC, all you might need are converters with the right plugs and polarity.


If you are physically unable to carry a large heavy battery (and sorry I missed that if you mentioned it) then you need to spend more money on multiple smaller power packs.

The OEMTools PPS-X has everything you need except enough AH, so even if you don't buy it, study the specs and output ports.

I think if you start with two of those, depending how often you can swap them and how much you use while doors are locked, two may be enough.

It is impossible for anyone to accurately predict how long you can run your devices from any low number of AH. Playing games, any GPU usage is definitely heavier than just email and office.

 

[Optimistic Paranoid]

Do you have a link?  What's a wall wart?

Wall wart is a slang term for those black boxes that plug into the outlet directly and step the 120 volt ac to a lower voltage and/or convert it to dc.

Same link you gave me.

https://www.amazon.com/gp/product/B0052OTB6S/

Go down to CUSTOMER QUESTIONS AND ANSWERS and work your way through the questions.  Down around question 12 or 13 you come to one about "I need to get a new ac/dc adapter".  The information was in the answer to that question

 

[Optimistic Paranoid]

BTW, what does LFI in your title stand for?

 

[DLTooley]

18.3 AH@12, probably around 15 usable. You should get several hours on the laptop with this. This is an emerging market and there are a lot of competitors. The charge controller for the solar connection is a critical part to evaluate. All of these I've seen have inverters which is a bonus but you should avoid using as much as possible. All of my devices are either straight 12v, usb 5v, or run off of NiMH rechargeables. (with a portable charger, like the Tenergy) The various competitors have different solar solutions and would be a good comparison point. They are pricey and you could do it for less with your own system, if compatible with the controller.

I'm waiting until I can get a 35-40ah battery at this same price. I don't need the inverter.

 

[Headache]

BTW, what does LFI in your title stand for?

Looking for info.

Sorry I was confused about the light. When I read "I took a look at this light" I assumed you looked at a different one and I was asking for a link to that one.

 

[John61CT]

What's a wall wart?

The adapter if you want to plug the laptop into 110V AC "shore power", AKA power brick sometimes the charger.

If you end up using an inverter (which I do NOT recommend, that's what you plug it into instead.

There will also be a 12V "car adapter", and that's what you want to work from a battery or power pack. But a ciggie port is a bit clumsy, better to just figure out the polarity, +/- which is inside the tip? and the size of the tip.

Then do the same for the 19V output (assuming that's what the laptop takes) from the power pack, and cobble together a wire that will connect one from the other, no conversion needed.

If your power source is 12V then you'll need a converter.

When you end up getting your power source lined up, I'd be happy to help with the details, very few tools needed if any, likely a pocket knife will do.

That's an example of what I meant by "some wiring" needed, stuff I'd teach my 7 y.o. daughter. If for whatever reason that piece is really too big a hurdle, I'll likely do it with her as a weekend project and mail it to you completed.

 

[John61CT]

Came across this, seems a good fit to me, likely "enough" for your daily use, lighter and less costly than other options. Anker is well-respected as a brand, and this seems to be a genuine sale ATM, buying direct so no warranty problems.

https://www.anker.com/deals/powerhouse2