Poke 2 - Battery Replacement?

[Glottis]

Hi there, having had no luck getting my Poke 2 problems sorted, I'm looking to replace the battery since that appears to be the main issue.

I'm in the UK and there aren't any easy-access repair services for it here.

As a result, I'd like it if anyone knows the specs/serial number/model/etc for a battery replacement that I search for.

In other words, does anyone know what battery it takes without me needing to rip it apart myself

[erayd]

The stock battery the Poke 2 comes with has a model number of CLP255875. There appear to be a number of replacement batteries for it available on AliExpress.

I've opened mine up to confirm the battery model number, but have not attempted to purchase a replacement battery for it, as I ended up buying a Poke 3 in the hopes that it would not destroy its battery the way my Poke 2 has (the Poke 2 battery was incapable of even booting the device after only a few months of usage). Sadly, the Poke 3 had battery issues out of the box, which also became progressively worse very rapidly.

I will never buy another Onyx device. The battery problems are a deal-breaker, which is unfortunate, as they are ideal for me otherwise.

If you are looking for a battery replacement guide for the Poke 2, someone has posted a good thread on reddit here. There is no adhesive around the edge of the device, just lots of clips - I found a thin guitar pick worked perfectly to open it, starting at the USB port - it was difficult to get that initial insertion anywhere else. Note that when you are removing the battery from the back of the screen, you need to be extremely careful with the flat cable linking the motherboard to the power button & LED. On my device, that cable was adhered to the back of the battery.

The adhesive used to attach the battery is two strips of quite strong double-sided tape. No heating is needed to remove it, but it is best to proceed quite slowly. I found that sliding a thin plastic playing card (*very* slowly, with lots of wiggling) between the battery and the metal plate it's glued to worked best.

[Renate]

Originally Posted by erayd

I will never buy another Onyx device. The battery problems are a deal-breaker, which is unfortunate, as they are ideal for me otherwise.

I am surprised, although it seems I've seen lots of battery replacement threads on the Onyx forum. Ok, batteries are a hassle, but they are not particularly expensive either. Actually, I've never replaced a battery on anything. By the time the battery has swelled it's time to do a battery-ectomy and either use the device in fixed service with a wired power supply or to just use it occasionally for regression testing.

I've had my Poke3 for a year now and never intentionally charged it. By that I mean that I do enough development and syncing that I never even pay attention to charge level. I think it's a great device and I ignore most of the Onyx stuff.

Oh, and you're right. Start at the USB jack. The back cover actually has a slot there and it's easy.

[erayd]

Originally Posted by Renate

I am surprised, although it seems I've seen lots of battery replacement threads on the Onyx forum. Ok, batteries are a hassle, but they are not particularly expensive either. Actually, I've never replaced a battery on anything.

It's not about the cost of the battery, but rather the time and risk (the devices are easy to damage) involved with replacing them, how fast they degrade, and the total lack of practical support from Onyx regarding them. They will not provide replacement batteries, nor do they provide any local service option, and no local third-party repair place in New Zealand will touch them - the only avenue open to me is to either DIY it with AliExpress batteries (which take a good 2+ months to arrive), or pay to ship the device back to China for service (which is quite expensive).

I want a reader that functions correctly, without crashing or failing to properly refresh the screen because the battery cannot supply the necessary current, and lasts for more than a few minutes of use. And I want it without having to pull the darn thing apart every few months to replace a battery that is not intended to be user-replaceable. That seems like a pretty reasonable set of expectations.

By the time the battery has swelled it's time to do a battery-ectomy and either use the device in fixed service with a wired power supply or to just use it occasionally for regression testing.

Poke 2 cannot operate in that mode; it requires a functional battery in order to boot, even if a charger is attached.

I've had my Poke3 for a year now and never intentionally charged it. By that I mean that I do enough development and syncing that I never even pay attention to charge level. I think it's a great device and I ignore most of the Onyx stuff.

That is great for you, but most buyers don't purchase these as dev devices. If they cannot handle normal usage as an ebook reader & perhaps a few light tablet tasks - which they cannot - then they are fundamentally unfit for purpose. They are certainly great devices, but the battery problem is not one that can reasonably be overlooked in most cases.

[Renate]

Originally Posted by erayd

Poke 2 cannot operate in that mode; it requires a functional battery in order to boot...

Most devices want to "see" a battery. It can be a thermistor or an ID resistor or I²C to a BMS. I just remove the battery cells themselves and reuse the old BMS (the tiny PCB inside the battery pack). You feed that 4V and it's as happy as a pig in ... stuff. I have a half dozen devices so outfitted. Some I modified straight out of the box. It's safer. Verizon had recalls for flaming hot spots.

Of course I realize that my perspective is not normal.

Here in the 21st century all manufacturers are crappy about replacement parts. I can't think of any tablet/ereader company that offers replacement batteries. Those suckers are glued in and if a user tried to remove one with a sharp screwdriver... Smart phones used to more commonly have removable batteries too. Not any more.

Still, the question remains: Are Onyx batteries statistically worse than others? Maybe we need a poll.

[erayd]

Originally Posted by Renate

Most devices want to "see" a battery. It can be a thermistor or an ID resistor or I²C to a BMS.

The Poke 2 requires something that can actually deliver a useful current - i.e. an actual, functioning battery, or some other power source connected to the internal battery terminals. It isn't just about what the device thinks is present, but rather that it cannot draw boot power from the charger. It only draws power from the charger once it gets far enough through the boot process to turn on whatever piece of circuitry is necessary to do so. If the battery can't provide enough power to get that far, you're out of luck. Terrible design, and the only device I have ever encountered that behaved this way.

I just remove the battery cells themselves and reuse the old BMS (the tiny PCB inside the battery pack). You feed that 4V and it's as happy as a pig in ... stuff. I have a half dozen devices so outfitted. Some I modified straight out of the box. It's safer. Verizon had recalls for flaming hot spots.

Of course I realize that my perspective is not normal.

Not practical for most consumers, but certainly a neat solution to the issue if it fits your workflow :-).

Here in the 21st century all manufacturers are crappy about replacement parts. I can't think of any tablet/ereader company that offers replacement batteries. Those suckers are glued in and if a user tried to remove one with a sharp screwdriver... Smart phones used to more commonly have removable batteries too. Not any more.

True, but it wouldn't be a problem if the battery actually lasted properly in the first place. If it was enough to cope with a few years of typical usage, as most such devices from other manufacturers are, then for almost all users replacing it wouldn't even be necessary.

Still, the question remains: Are Onyx batteries statistically worse than others? Maybe we need a poll.

Anecdotally, definitely yes, and my own experience also points that way.

Objectively, I don't know - I'm not aware of any data that could usefully answer that question, although I'd love to see it if it exists somewhere public. I have seen a much higher number of threads for Onyx devices with battery issues than would be expected if they failed at rates more typical of other devices, though.

[Renate]

Maybe I've stated that poorly. Every device requires large start-up current that is usually in excess of what the USB can deliver (unless it's a Type C wih PD). In any case, what I meant is you can't just connect a power supply to red and black of where a battery used to go and get the thing to boot (unless it only uses two wires). The 3rd and 4th (if present) have to be connected to something that say, "I'm a battery!" Here's a photo of my Verizon hot spot which I'm using right now. Before it ran hot (which increases noise in the front end, killing performance in marginal areas). I removed the battery, the front window, the display and installed a heatsink. It runs much cooler now.

Here's a plot I did of something (I forget what) but you can see that it peaked at a good 1.4 Amperes when booting! Most devices hit at least 1 Ampere. Edit: I think that's my Nexus 7. I checked my Moto E5 and it hit an Ampere.

[erayd]

Originally Posted by Renate

Maybe I've stated that poorly. Every device requires large start-up current that is usually in excess of what the USB can deliver (unless it's a Type C wih PD).

That doesn't sound right. If it were, devices powered via USB only (with no battery at all) would not be a thing - and yet they are ubiquitous, including devices with a high startup current.

In any case, what I meant is you can't just connect a power supply to red and black of where a battery used to go and get the thing to boot (unless it only uses two wires). The 3rd and 4th (if present) have to be connected to something that say, "I'm a battery!"

I think we're on the same page now :-). I did initially think you were saying that you could chuck something there that *appeared* to be a battery, but delivered no useful power. The Poke 2 is the only device I have ever encountered that *requires* battery power (i.e. useful current, not just battery presence) to at least partially boot before it can start to utilise power from the USB port.

Here's a plot I did of something (I forget what) but you can see that it peaked at a good 1.4 Amperes when booting! Most devices hit at least 1 Ampere.

Most USB chargers supply at least 1A, and modern ones a lot more than that.

If you were trying to run the thing from a 500ma computer port, I could see your point... but that isn't a realistic limitation when we're talking about chargers.