Ozark Trail 500 Lumen Lantern - Mod guidance?

I was at Wal-Mart yesterday, and they had the last Ozark Trail Deluxe LED Lantern in the store on clearance for $5.

If it gets anywhere near the claimed runtimes, it’s probably worth it as is (21 hours at 500 lumens, 720 hours at 30 lumens).

But, at $7 for 4 Duracell D’s, I think I would prefer some changes.

Here’s a photo or 2, just to prove it happened:

What I’m wondering is this: is it feasible to add the ability to run off of lithium rechargeables (my yeti 400, and an external bank (not at the same time)), but keeping the ability to run off D cells.

I’m thinking a cylindrical dc connector inside the battery compartment that I could plug 6V into. The D cells are 4 in series.

My question is, what’s an easy way to get 6V? Most usb power banks are 5V (right?). My Yeti has USB and 12V DC. If I bought or built a 12V 18650 powerbank, I would only need one 12v-6v DC converter, but I’m not sure exactly what would be good for that.

It might be easier to just get some NiMh D cells, but that’s not cheap, either and only useful for this lantern. So, meh.

I do see some 12 V power banks on aliexpress and amazon.

Based on the runtimes and wikipedia’s numbers on D cells, I’m guessing a 3A dc converter would be more than sufficient, but my electronics knowledge is atrophied.

My other concern is that if one of my kids plugs in the lantern with alkalines in it, I don’t want it catch on fire trying to charge them. So either a circuit(would a diode do?) to prevent that, or physical placement of the connector so it’s impossible to use with the batteries in. Am I being paranoid?

Those of you that are better at this than me, what you would you do? Or what do you suggest?

my opinions, worth what you pay? nothing?

still… 6v isnt like you put a budget dmm on it… and SEE 6v. its “nominal” 6v. The same way a 2x4? is really 1-5/8ths x 3-5/8ths… like that? actual isnt “nominal”.

the “real voltage” after some run time? could be as low as 4v… under load? could be “as high as” 6v under no load with brand new cells.

my guess? if its series? and not a boost drive in parallel? is that it would prolly/maybe “take” 1/2/3 or 4” liths in parallel… thats just a hunch without testing it.

you might well, if these assumptions are correct? re-wire the series connections to all parallel, and maybe squeeze in 4-26650s in parallel, lol…

if this is all good guesses? thena powerbank providing “5v” would acually be 4.5 to 5.5v at any one moment in time, within the range of acceptable voltages… if itsa beefy powerbank? might not sag under load as bad a 4-D-in series thing under load on high for a while…

i’ll let someone else chime in, i’m making too many assumptions already, just WAGs = wild @$$3d guesses”

Good point. You prompted me to try this, and it seems to light up just fine with one 18650. So, 5V would probably work great. That makes things simpler. Thanks.

To put 26650s in I would have to make a new bottom cap. They’re just too long, and the springs don’t give me any room to work with. They’re leaf springs with very little room to move. I had tried that, and the threads on the cap won’t even engage with a 26650 in the D compartment.

Now to take it apart ….

Is the light as cool white IRL as it appears in the above pic? I have the Core version of this lantern and it’s more neutral in tint.

Not quite, but it’s pretty cool/blue. It’s a phone pic.