Single LiFePO4 cell inverter; is it possible?

[SeaGal]

Random thought...

Would it be possible / feasible to build a PSW inverter (230V) to be powered off a single LiFePO4 cell, rather than the usual 4-cell (12V) configuration. Or does one exist to buy? Say in the 500W to 1000W range?

Was thinking...
- I have a spare LF280K
- It would be good to have a portable mains AC source for powering things were cables won't reach
- Being one cell would mean it is very portable
- Being one cell could mean it can be charged without the complication of BMS cell voltage management

But would obviously need to draw 200A to 300A (+losses) to provide 600W-900W output, so maybe not do-able?

 

[ericfx1984]

I mean possible? Everything's possible... If you can build one at 12 volts you can certainly build one at 3.2

But I guess the real question is what's the point? It's going to cost you a lot of time and money to build something for that voltage... But... A fella could build a small 4S battery or even buy one ready to roll and purchase an inverter for next to nothing

This is one of those cases we're building just doesn't make sense... Purchasing something that's ready to roll off the shelf would be the hot ticket

 

[SparkyJJO]

That would be a lot of stress on a cell. That's a lot of current draw. And it wouldn't run very long.

 

[SeaGal]

But I guess the real question is what's the point? It's going to cost you a lot of time and money to build something for that voltage

I like a challenge and time is less of an issue... but agree, not if it would cost a lot of £££.

That would be a lot of stress on a cell. That's a lot of current draw. And it wouldn't run very long.

True - think 1C discharge is max for the LF280K.

 

[Partimewages]

Salesman always says with enough money everything is possible!

 

[MisterSandals]

- I have a spare LF280K

I've been here, often with 2 or 3 extra cells. As much as i felt it is a waste, when the time comes that you have a flaky cell and have a matched replacement on hand, it makes it worth while.

 

[SeaGal]

As much as i felt it is a waste, when the time comes that you have a flaky cell and have a matched replacement on hand, it makes it worth while.

exactly the reason I bought 17 in the first place. You're right (as always) - I'll keep it for the purpose it was bought for

 

[42OhmsPA]

I've thought about using my spares to power some leds / make night lights / tinker.

 

[Warpspeed]

Yup.
I bought 32 cells even though only thirty can fit into my battery box.
One day those two spares might come in very handy.

 

[SeaGal]

Yup.
I bought 32 cells even though only thirty can fit into my battery box.
One day those two spares might come in very handy.

Thanks... Well, that's doubly confirmed it then... (after @MisterSandals feedback)...

If the Warpverter guy isn't giving me a circuit diagram for a 3.2V to 230V micro-warpverter, then it ain't a good idea ?‍

 

[Hedges]

Boost converter for USB charging port.
Boost to 12V for critical loads backup (common for many communications boxes).
Of course, want diode or other arrangement to let AC adapter also power those loads.

I plan to do similar with a spare 12V AGM battery.

 

[shavermcspud]

To chime in, I made a really small but smart "UPS" with a boost converter / charger from a single 3.2V LFP, runs my raspberry pi just lovely

 

[curiouscarbon]

To chime in, I made a really small but smart "UPS" with a boost converter / charger from a single 3.2V LFP, runs my raspberry pi just lovely

awesome, DC UPS is perfect for raspi ?

may i ask, how are you charging the single cell; which chip/device supports 1S?

assuming there's a separate boost converter to go up to 5 volts..

thanks for sharing!

 

[chasingentropy]

Random thought...

Would it be possible / feasible to build a PSW inverter (230V) to be powered off a single LiFePO4 cell, rather than the usual 4-cell (12V) configuration. Or does one exist to buy? Say in the 500W to 1000W range?

Was thinking...
- I have a spare LF280K
- It would be good to have a portable mains AC source for powering things were cables won't reach
- Being one cell would mean it is very portable
- Being one cell could mean it can be charged without the complication of BMS cell voltage management

But would obviously need to draw 200A to 300A (+losses) to provide 600W-900W output, so maybe not do-able?

This seems like a fun project. Totally doable you can avoid thermal limits by running two flywheel boost circuits (one dc one ac) in series to get 3.2v dc->30v dc->120vac the immediate issue i see is a 500va load would present a sustained draw of at least 170amps on the cell.

Two or three 3.2v cells in parallel would still avoid the bms but would allow for the current draw.

 

[time2roll]

Far easier and less money to buy three more cells.

 

[Warpspeed]

Far easier and less money to buy three more cells.

Three cells of one third capacity, should cost hardly any more than one huge single cell.
And a single cell would need to be truly huge to be of any practical value.