{"id":17790,"date":"2017-11-13T15:13:07","date_gmt":"2017-11-13T14:13:07","guid":{"rendered":"http:\/\/www.recantha.co.uk\/blog\/?p=17790"},"modified":"2017-11-13T15:41:15","modified_gmt":"2017-11-13T14:41:15","slug":"pijuice-portable-battery-power-for-your-raspberry-pi-a-review","status":"publish","type":"post","link":"https:\/\/www.recantha.co.uk\/blog\/?p=17790","title":{"rendered":"PiJuice – portable battery power for your Raspberry Pi – a review"},"content":{"rendered":"

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The PiSupply PiJuice<\/a><\/strong> is finally here!<\/span><\/p>\n

What is the PiJuice?<\/span><\/h2>\n

It\u2019s a battery power pack HAT for your Raspberry Pi.<\/span><\/p>\n

The Review<\/h2>\n

Tim Richardson<\/span><\/a> (<\/span>@Geeky_Tim<\/span><\/a>) has joined me on this review to give his insight, so we\u2019ll be moving back and forth between our two viewpoints. We were handed the PiJuice review bundle at a recent CamJam<\/a> so decided to do a joint review!<\/span><\/p>\n

Some background<\/span><\/h2>\n

It all started <\/span>over two years ago on Kickstarter<\/span><\/a> as a really good idea that went awry. \u00a0It\u2019s taken Aaron Shaw and the team that two years to get the final product to their backers. \u00a0A lot of that time, unfortunately for both them and us backers, they have had numerous issues which have been endlessly discussed in the over 2000 comments on their <\/span>Kickstarter pages.<\/span><\/a> We won\u2019t go over those issues again here as some is speculation and it\u2019s hard to know fact from fiction; but the product is finally here and (almost) ready to ship to backers and to go on general sale. So, let\u2019s take a look.<\/span><\/p>\n

The Hardware<\/span><\/h2>\n

Tim<\/span><\/i>: The final product has certainly not been rushed. \u00a0It is a very clean circuit board that will plug into all 40 pin Pis. \u00a0You can power your Pi from the battery (a Motorola BP7X 1820mAh phone battery) alone, or by powering the Pi directly, leaving the battery as a backup, power the board itself, or both. \u00a0Why would you want to power both the Pi and the board at the same time? \u00a0The PiJuice allows you to run the Pi from the mains while you use another supply, be it mains or one of the solar panels either available from PiSupply or elsewhere, to keep the battery charged. \u00a0Then, if you lose power, the battery will automatically take over and keep your Pi running. \u00a0Within the first few minutes of testing I wanted to swap the power over from one supply to the other and unplugged the Pi; it kept running happily without interruption.<\/span><\/p>\n

Mike<\/span><\/i>: I, too, was impressed with the hardware. The main PiJuice board is absolutely gorgeous on the underside with a huge amount of components squeezed in. I even love the colour of the PCB (a kind of \u2018hot pink\u2019) which closely matches the packaging. It\u2019s a nice, completely irrelevant touch. I love it.<\/span><\/p>\n

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The battery is a hard-cased Lithium Ion affair, rather than a LiPo (which tend to be a bit\u2026 squishier\u2026) so is potentially much safer for it.<\/span><\/p>\n

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The board is fully hot-swappable. I placed it on the Pi while it was turned on and powered by a PSU and it worked fine. I removed the PSU, it was still \u2018on\u2019. I removed it in the same cavalier fashion with the PSU plugged in and the Pi remained up and didn\u2019t reboot or anything.<\/span><\/p>\n

I have to say, I\u2019m not crazy about the PiJuice automatically being \u2018on\u2019. As soon as I plugged it into the Pi (with the Pi off), it started up with no warning or any kind of button press. It\u2019s a small thing, but given that I\u2019d just finished testing the GoPiGo, which has a power-on button, it\u2019s something I noticed.<\/span><\/p>\n

Another thing to say is that the small buttons on the side of the PiJuice are labelled in the most tiny font imaginable, due to the space available. They also seem in a strange order: SW2, SW3, SW1 from left-to-right.<\/span><\/p>\n

I experienced a <\/span>possible <\/b>interaction with the Pi 3\u2019s wi-fi – my connection was quite a bit weaker with the PiJuice on top than without it. That might be a result of where I was (at the bottom of my garden) or it <\/span>could <\/span><\/i>indicate some RF interference by having the battery and circuitry so close to the Pi 3.<\/span><\/p>\n

The LED on the side still flashes occasionally when the PiJuice is not plugged into the Pi. I would prefer to have had some way of turning it completely \u2018off\u2019 and not draining the battery at all, but that\u2019s a small thing: you can always remove the battery; in fact, that\u2019s probably the best advice if you want to ensure that the PiJuice is truly \u2018off\u2019.<\/span><\/p>\n

Tim<\/span><\/i>: With the growth of the IoT (Internet of Things) over the last few years, being able to power your projects even in the event of power failure is going to be extremely useful (although loss of network power may cause you problems!). \u00a0With many smaller devices now being battery powered, being able to continue to have a Raspberry Pi hub on your premises is going to be essential.<\/span><\/p>\n

The PiJuice pass-through header means that you can plug another HAT on top of the PiJuice HAT. \u00a0The three buttons and two LEDs can be configured to do what you need them to, and there are two further interfaces that I have not yet found full documentation for, but to be honest, this is not unusual for unreleased hardware; I am sure PiSupply will supply more information in due course.<\/span><\/p>\n

Mike<\/span><\/i>: Even though the battery is quite thick, HATs and pHATs will still fit on the extended header provided. I tried it fitted with a HAT that had a low-profile header (in my case, the <\/span>Pimoroni UnicornHAT<\/span><\/a>) and, of course, with a full-sized header, like on the <\/span>RasPiO Pro HAT<\/span><\/a> (the one with the pins in the correct order and the breadboard on top) and also the <\/span>Pimoroni Explorer HAT<\/span><\/a>. An extended header is, of course, an old solution to the issue of stacking HATs, but it does work very well here and the battery doesn\u2019t get in the way unless you have a lot of components sticking out on the bottom of your stacked HAT\/pHAT. The good news is that the PiJuice uses only I2C and power pins, so there is no clashing of hardware. Even if there <\/span>is<\/span><\/i> an address conflict, the PiJuice\u2019s I2C address is configurable via the software package, which we will now look at.<\/span><\/p>\n

In use, the power supplied by the battery is steady and reliable. Here is a quote from <\/span>The MagPi review<\/span><\/a> about how long the battery lasts:<\/span><\/p>\n

\u201cWe performed a simple uptime test with a Python script that periodically logged how long the Pi had been running. On an idling Pi 3, it averaged around 4 hours. A little shorter than we\u2019d hoped for, but on a Pi Zero or A+ you should be able to achieve near double that.\u201d<\/span><\/p><\/blockquote>\n

Now, of course, you can get very high-capacity USB power banks that will last longer than that, but if you\u2019re looking for a more compact solution, the PiJuice has a lot to recommend it.<\/span><\/p>\n

The Software<\/span><\/h2>\n

Tim<\/span><\/i>: Setting up the PiJuice is as simple as it can be; stack the PiJuice on top of your Pi and that is it. \u00a0As long as the battery has charge, the Pi will run. \u00a0However, there is a control package that will enhance your experience, installed with the simple one line:<\/span><\/p>\n

sudo apt-get install pijuice<\/span><\/pre>\n
This will install the PiJuice configuration tool that will show you how much juice you have left, whether it\u2019s charging and allows you to configure how the supply and Pi reacts to various events. These events include a low power warning and a \u201ccharge-reached\u201d trigger. You can also start your Pi on a schedule, and program the three buttons on the side of the PiJuice to do what you\u2019d like them to do such as shutdown, reboot or any other action.<\/span><\/p>\n
Mike<\/span><\/i>: After you\u2019ve installed the software, you get a nice little battery-level icon which appears near to the Bluetooth and wifi icons on the taskbar of Raspbian. Hovering over it gives you the current battery level.<\/span><\/p>\n
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Right-clicking the icon lets you into the configuration software where you can:<\/span><\/p>\n