XTAR PB2 thread

I mean none of the batteries I have personally will fit. The only unprotected batteries I own are 30Q's but they are button tops. Most of my batteries are protected.

Oh ok… flat top are cheaper!!

Thank you! What would happen in following situation in the PB2?

Mode: Discharge (e.g. charging up a phone via USB)
Channel 1: Sony VTC5A, capacity 2.600mAh
Channel 2: Samsung 35E, capacity 3.500mAh

Now, being discharged in parallel those cells would always have the same voltage, right? Sorry for raising a stupid question but how does this work with cells of different capacities and what happens when both cells reach something like 2.8V? I always thought it’s no good idea to combine cells of different brands and different capacities regardless whether they’re being used in parallel or in serial.

Think of it as two water containers in parallel, one with a larger diameter than the other. An imbalance would be created IF they were being drained at the same rate, by a separate tap at the base of each, but that is not equivalent to what is happening here.

In this scenario the containers are joined by a thick pipe at the bottom, and are being drained by a single tap. Their levels will stay exactly the same until they reach the cutoff, no imbalance, no issue.

Alright, I guess I got you. Thank you! So, I have to imagine the battery drain of both cells like this?

That is exactly how I pictured it.

Different scenario for the charging circuit though. Take that same diagram and put one way valves leading from the central pipe to each tank , so they can be at different levels but can only fill, not empty, so they won’t affect each other at all.

Now pump the liquid in slowly, it will go to the point of least resistance, filling the more empty container first, then keeping both at the same level and filling them together when the pressures equalize.

In both scenarios, the level or pressure is equivalent to voltage, and the volume of liquid and container is the charge and capacity respectively.

Im loving my pb2! My previous power bank holds 8x 18650s and is big, bulky, and doesnt charge my phone as well even though it claims 2 amps output.

This pb2 fits in my pocket, my phone charges fast, and its got a slick design. I often fidget with the magnetic door while charging my phone and its very satisfying for some reason.

I don’t know how the ports negotiate charge rates, but I have a 4 bay Soshine which is probably a rebadged Tomo, and the curious thing is that there is a 1A and a 2A output port, yet the 1A port uses a faster rate with my phone than the 2A, but only the 2A will deliver good current to my tablet.

Same… I like mine too… it even charge my Samsung wireless charger quickly… very good product.

good power bank, not so good charger
because of not fitting protected nor button top cells

I got one of these for review from Banggood! Here’s the review link and there’s a promotion and code for those who want to buy one (all non-affiliate).

BTW, I do like this PB2 a lot :heart_eyes:

I do have a question though! I wanted to buy some batteries with large capacity (3400 or 3500mAh).
I’ve been thinking about the Sanyo GA, but recently saw the Samsung 35E and started wondering which would the the best.
Do you have any input on any of these? The batteries will mostly be used to work with the charger and, occasionally, to put in flashlights (non high drain)!

Any help is appreciated :wink: Thank you!!

Just take the 35E.

At most with a single cell, you are going to be drawing 3.5A, and the 35E is great at that much current.

So actually, just pick whatever is cheaper in this case.

Thanks for the answer BlueSwordM!
Actually I think that - at least in AliExpress - I’ve seen the Samsung cheaper that the Sanyo!
I may pull the trigger on a couple of them!!!

BTW, has anyone tried unprotected button top cells? I only have flat tops, so I don’t know if the button tops will fit as well!
Thank you again :wink:

Is my PB2 faulty?

I have good working LG HE4 for these but the charger sometimes get wonky and restart the charge as if my usb power aren’t capable of delivering power.
The USB out couldn’t charge my Oneplus 5T so I assume it cannot draw out more than 1A but I’ve read others charging modern high drain phones with ease

either my cells are not good or the pb2 is faulty?

But overall love the PB2 as it charges my cells really fast when it’s working properly. Cells that are low resistance are able to get topped up 100% real quick without heating the cells.

Just got mine yesterday and tried with button top 30Q, it was a very tight fit, not easy to remove, so I removed it and using Pana flat tops instead.

The PB2 will not charge low drawing devices
It will not charge my Blutooth earphones/MP3 players/10440/10180 lights/Nitecore TIP/TINI
So I have to carry TWO chargers when I travel???
I think NOT.

I love the idea of the PB2, but it misses the mark in a few ways.

There’s 3 things that would make it just about perfect:

- Type C input

- Auto-restart when the voltage drops, to make it play nicely with solar panels

  • Output toggle like Xiaomi uses to let you charge low-draw devices without cutting off the output.

And then of course, it’d be nice to see a 21700 version in the future.

I have an idea that your plan to provide unlimited power to your TINI is not going to happen.
The PB2 will not charge up the TINI nor the TIP let alone provide prolonged power.

well, I will list this, as it does not provide an adequate solution to the problem.

Yes… I found out it wasn’t charging a mini tini.