Power for Bed in Emergency

[Toro]

With the weather in Australia now starting winter, I'm looking into a battery back up for my bed as the one connect to the bed ain't worth a crap.

Can anyone please pass on your suggestions or advice in what you've done for yourselves?

Was looking into a portable power station?

[Burgerman]

Thats easy. I have a cable that I connect to its input with an anderson connector. It runs off 12V anyway. So connect that to a unused wheelchair battery if needed. Or my carer will. You could fit an XLR connector, with 3A fuse, and use this too. Now that is 24V so in my case I would need to add a 24V to 12V inverter from eBay inline as well. But my chairs have a 12V anderson (2 in fact) anyway. So I wold connect to one half of the battery. Thats OK if I also charge them in parallel at 12V as both will be correctly charged. Which I do.

Depending what voltage your bed runs on your solution may be slightly different. For e.g if it NEEDS 240 or 110V you need an inverter for AC from your chair or battery. Etc. All pretty easy and cheap. You could also make a small pack for it from 18650 cells. The number of cells needed would depend on its required voltage.

[expresso]

https://www.amazon.com/APC-Battery-Prot ... r=8-3&th=1

had this one on my bed for many many years - lasted longer than i expected - now the battery finally died i think - i have another one 750 version of this one little bigger battery for many years also -

simple plug and play - the 600M battery died or unit not working - searching for a new battery - not even worth it - since you can buy the whole thing again for extra $20 anyway - it can also be the unit failed along with battery so i have it sitting on the side - deciding to junk it soon

i leave the larger unit instead - still going fine - when that one dies - i decide if its worth replacing the battery or just get a little lithium power bank also - they lighter then lead bricks - i have two old batteries lead also with inverter - never had to use it over a decade - its that one off moment that something can happen

like hurricane sandy here - only time i ever had to use it -

[Toro]

Bed is run on 240.

Power very rarely goes off here, very few power outages, though being a quad, it's necessary to have power and back-ups for running equipment.

Both suggestions could work, I might go with both ideas as it will give me options and also run a laptop in the event of a power outage.

[Burgerman]

When you say bed is run on 240, they all are (or 110). But thats not normally correct. The wall wart or power supply does. The bed itself is generally using a low voltage DC of 24 or 12V. And its HERE you tap in, supply a bit of battery power. Add a simple diode so that the bed doesent charge the battery. And then when power goes down the bed will run automatically from the battery. Or your chair. Or whatever.

Your chair or a old battery under the bed will also directly run a laptop too. 12/24V laptop power supplies are available. Cheaply.

[Toro]

Lol sorry I mean power is 240, yes bed is 24v.

[Burgerman]

Then a simple cable that plugs into your XLR powerchair port at night means that your bed will work great even when the power goes off.

You need XLR, 3A fuse, a single Diode in the cable so that the beds power supply doesent try to charge the chair.

Totally simple, easy to make, cheap. And reliable with nothing else required.

You can do the exact same thing with 7 cells series connected (18650 cells). But quality 3Ah LG or other known brand like Samsung, Panasonic. That will work for days. Charge once every 6 months to be sure. Use a simple ni-cad - lithium 18650 cell charger. Loads on ebay.

Or https://www.aliexpress.com/item/1005005 ... vfkRbYW4R0

No chair needed.

[Toro]

Yes I prefer to have it separate from the wheelchair. It's best for me to have it's own usage for the bed.

Is Li-ion safe?

[Burgerman]

I wouldnt sit on top of them in a wheelchair. And so in that case considering the the larger quantity no.

But its in your phone, and your laptop. Do you worry about them there? Those have been problematic in the past. Many recalls. And fires. But in small sizes its not that bad of an issue. And less likely to be a thermal runaway problem. Lots of surface area to Ah. Do you have your phone or laptop in your bedroom?

If you do worry, do the same thing with LiFePO4 pack instead. Or lead. 2.5Ah upwards will be plenty on lithium. 4Ah and upwards for lead. Will work for days.

[Burgerman]

Or get a manservant. Or better still an ornamental young blonde, pretty female one. No electricity or complication needed. And something interesting to look at.

[Toro]

Lol I got a couple of those pretty female ones, but still need the power to see and enjoy.

[MobileOne]

I’m in Aus and use an Allpowers 606Wh power station for lots of different things. Has a 700W sine wave inverter which can charge various electric mobility devices I use plus charge phones, ipad etc from USB A an C ports. Can connect a std 110W solar panel to recharge if there is no grid power. Will make toast with a 2 slice toaster if required. Has a couple of LED lights to light up the room built in and a 12V accessory socket. Weighs about 5.5kg and is compact enough to carry around, cost $A560. A smaller version with a 288Wh battery and 300W sine wave inverter is under $A300. Better brands out there with longer life (LiFePo4) batteries but they all cost a bit more.

[Burgerman]

I realise that you were not intending this for charging wheelchairs. But lets do some maths for that scenario anyway.

Since it only has a small 20Ah battery @ 24V, and its 85% efficient then at best it can charge just 15Ah approx back into your typical mobility device. So thats about 1/4 of whats needed to fully charge a small 60Ah powerchair battery.
So it might keep the lights on, or run your laptop or electric bed but its not going to charge a powerchair.

It might be a good plan for camping etc. A much bigger capacity one would be useful as a thing to charge a powerchair. Say 4 or 5x the capacity (100Ah?).

Lets see.
An 80Ah set of typical lead bricks like in my backup chair takes 80Ah x 28.80V = 2304 watt hours to charge. Plus 15% (quoted inverter efficiency) + 15% battery and chargers recharge efficiency loss, means you really need 2304 + 30% capacity in watt hours to charge to 100%. So the battery in your device would need to be 2995 watts. Or 3000 Watt hours. Or if you are charging a set of 230Ah lihium batts in your chair that would need to be a huge 7160 watt hours. Or about 14 times bigger than your sall portable one!

Since a lithium chair with 230Ah cells is already a massive storage bank, with 5,500 watt hours stored, it may be better to use this as your (10x bigger) storage battery and just plug a portable inverter into that to run everything including my house from. All my chairs are in fact wired so that I can use them as a battery / power storage medium. So if the power goes off, I can run everything from my powerchairs. Th opposite way aroud to what you do in fact.