Flexopower 444 lithium

Has anyone got their hands on one of these yet? Seems to have all of the options I would want but not sure on the quality. Wonder how it would compare to a yeti 400 lithium? I’m looking to run an arb 50 and just general weekend camping use. My interest in this type of power pack is the ability to move setups between my taco and burban depending on what I’m doing. Any recommendations on a similar power pack in this price range?
 

john61ct

Adventurer
All of them are IMO very poor value, often very hard just to determine the actual specs or batt chemistry used.

Being able to replace the internal cells is essential.

Get bare LIFEPO4 cells - maybe LiPo if only to be used occasionally, choose the ports / electronics to suit your needs, and buy a Pelican knockoff box to enclose it.
 
I do agree with you that a better/more capacity system could be built although prob not for the 349$ that the 444 is going for but you would end up with more capacity but I don’t think you could package a home built one as well. I need to do more research before I decide but portability is a large factor for me.
 

jonyjoe101

Adventurer
that looks like a good deal compared to the goalzero 400 lithium (cost 700 dollars), they are both in the 40ah range. The goalzero uses li-ion cells (cylindrical laptop 18650) the flexopower uses lithium polymer which are flat cells (like cell phone batteries but larger). They both are fully charge at 12.6 volts and 10 volts at 0 percent. It will give you usable power all the way to 10 volts then the bms will cut the output.

I don't think you can build your own and make it as small as the flexopower, I built a small 27ah li-ion pack and all the wiring takes up alot of space, and I didn't even add an inverter since it would make it even larger. If you use lifepo4 you will double the size of the pack for the same capacity as a small li-ion pack, lifepo4 cells are giant heavy cells (about the size of a D cell but heavier). Even though these packs operate in 11 volt range most of the time, thats still quite usable, I use my 27ah to run my roadpro cooker (11 amps) they will easily run a 12 volt fridge. On the video they use the flexopower to run a electric drill, so the inverter is quite impressive.

It says it charges at 6 amps, take 6 hours to fully charge. But one thing I don't like is that it only has 5 led's to tell you the battery status. For lithium a percentage gauge would be better. Also from my own 27ah li-ion battery I found out , to fully charge you need to charge at 2 amps or less, When I fast charge at 8 amps, it always stops charging at 12 volts. Thats why a percentage or even a voltmeter is important, so you know if you really got a full charge. They last longer if you don't fully charge but I prefer to get every AH out of my lithium packs. The bms can be overly sensitive in lithium packs and when fast charging will shutoff whenever it sees 12.6 volts or a cell that is too high.

Lithium is expensive but sometimes you do need a small batterypack you can take with you, I have a 220 ah lifepo4 house battery, and 2 smaller li-ion packs 65ah and the 27ah. The 65ah was too big, thats why I built the smaller 27ah.
 

Happy Joe

Apprentice Geezer
...Looks like the market is (finally) responding to give us more reasonable Li battery packs.
Hopefully when this, current, lead acid battery finally dies there will be even better battery w/inverter packs on the market. (the Flexopower 444 is close).
The Flexopower 444 lithium seems a bit on the large side though @ 12x5.3x7.3 when my DIY 30 AH lead acid unit is approximately 8x5.2x7.5 (including 80W inverter).
When Jeep camping; bulk reduction is a high priority.

Enjoy!
 

Chris Boyd

Explorer
...Looks like the market is (finally) responding to give us more reasonable Li battery packs.
Hopefully when this, current, lead acid battery finally dies there will be even better battery w/inverter packs on the market. (the Flexopower 444 is close).
The Flexopower 444 lithium seems a bit on the large side though @ 12x5.3x7.3 when my DIY 30 AH lead acid unit is approximately 8x5.2x7.5 (including 80W inverter).
When Jeep camping; bulk reduction is a high priority.

Enjoy!
Sure, but weight is also a concern, and I’m sure the 444 at 5.5kg (12 lbs) for 40 Ahr is a bit lighter than an equivalent AGM used in DIY. Advantages of lithium are the straight curve power delivery vs the 20 hr rate curve of the current sealed lead Technologes. I’ve built plenty of DIY boxes for radio gear...

I didn’t really know about the 444 before this thread, but its interesting and I think the price point for it is quite good given the level of integration with the inverter and charge controller.

I’ll be happier when we can get lithium box batteries similar to what Australia is starting to deliver similar in size and construction to our current AGMs. Then I might DIY one again.
 

john61ct

Adventurer
Beside price per watt hours, I would look for (in order of priority)

reasonably priced replacement of the internal cells, preferably use of OTS generic form factor & chemistry like cylindrical LiFePO4, and ideally from A123

design around a dis/charge rate near what the cells are designed to accommodate, ideally at least 1C

and ability to set charge voltage and LVD setpoints so the owner can strive to maximize longevity of the cells.
 

Happy Joe

Apprentice Geezer
Due to camping in the small TJ Jeep, volume/bulk is more important than weight for me (a somewhat rare special case).
If I needed to replace the AGM right now, I would strongly consider the 444 (althougth the ~$250+ difference in price would probably see me staying with lead acid.... personal choice... (It works well for me even though 30-35 AH is not enough for a fridge).

Enjoy!
 
So it seems like there are many options to build yourself, obviously, but this seems to be packaged well. I am also curious about what battery it is running and what warranty and repair work would look like. I'll try to call flexopower tomorrow and see if I can get any info. They seem to get decent reviews in South Africa so who knows. Hopefully they will stick around the US and I wonder if Expedition Portal will do a more in depth review of this product since Flexopower sponsors this sub forum.
 

john61ct

Adventurer
Try to get the actual cells used internally, as in e.g. ICR18650-30A, which is Samsung

Or at least the specific chemistry, e.g. LiCo, NMC, LiMN etc
 
i just got one since it seemed to be a good package that checked the boxes. I’m in need of a battery/inverter combo to power my CPAP. Yes, I’m aware that there lots of models out there that are powered via DC or a DC/DC converter. My unit isn’t one of those though and i don’t have the money to get one since it wouldn’t be covered by insurance. It has run my F&P Icon for a couple nights now - this isn’t on low power mode (which I forgot to turn on)

I enjoy camping but my wife doesn’t like me going without my CPAP.

Here is the power pack with my CPAP for size reference. 508532
 
I can say that it feels solid and substantial- to use the line from Jurassic Park: “Are they heavy? Yeah. Then they're expensive. Put them back”

Here is the sticker on the bottom :
508560
 
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So I was able to contact flexopower and they warranty the unit for one year and can service it after that period is up. They then say that the battery is non replaceable so I’m not sure if they mean by the consumer or at all. I just sent them another email to get some clarity on that. The cell is a Skyrich model 9059156, UL 1642 approved, NMC. If anyone could translate if that’s good or bad let us know.
 

john61ct

Adventurer
Company http://www.wanmabattery.com/eng/company.asp

Chemistry N:MC aka INR or LiNiMnCoO2

Probably a pack of 18650s inside.

More mainstream examples: Sony (now Murata) VTC5, LG HE2, Samsung 25R

Higher energy density than LFP, but much lower lifespan.

If used at high C-rates, and allowed to draw down to BMS cutoff each cycle, might get say 300-600 cycles.

And much more at risk of "unexpected thermal runaway events"
 

kmroxo

Observer
I just ordered one. The current $349 is the introductory price per the company and it will have a normal retail of $512 after the initial supply is gone. They are also offering free standard shipping right now. I was originally looking at either a custom built portable system or a Goal Zero Yeti 400 Lithium until I saw this. I’ll take the gamble on being an early adoptor for the price discount. I just purchased an ARB 50 fridge and this will be the power source when it is in the car and the car Ian not running and when stationary at camp. I may add a solar panel to the system in the future as well.
 
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