Bug #362

Need 2.5 hr battery for Pi, USB hub and projector

Added by Hammel over 6 years ago. Updated over 5 years ago.

Status:ClosedStart date:26 Jul 2014
Priority:ImmediateDue date:
Assignee:Hammel% Done:


Target version:PiBox - 0.11.0
Severity:04 - Low


Here are some ideas:

  1. http://www.iomagic.com/collections/smartphone-tablet-accessories/products/rescue-power-twinpack-2200mah
  2. http://www.adafruit.com/products/1390
  3. http://www.ebay.com/itm/New-USB-2-0-male-to-USB-male-and-female-splitter-Cable-for-data-and-power-/180873054040

If I use a batter to power the UUGear USB hub and then split that power line to the projector that might be good enough.
Still have a cable to each device inside a box but I could have a single cable to the box to recharge it.


#1 Updated by Hammel about 6 years ago

  • Status changed from New to In Progress
  • % Done changed from 0 to 10

Ordered IOMagic Rescue Power Twin Pack today.

#2 Updated by Hammel about 6 years ago

  • % Done changed from 10 to 30

Received the twin pack yesterday. A single battery was connected to a UUGear 7 port USB hub that powered the RPi model B PiBox Media Server. The batter was more than 1/4 used in about 1/2 an hour, meaning it would never be able to sustain a full length movie with the UUGear port attached.

So the Media Server will need to be plugged in full time. That's what I had originally intended, with the Media Players being mobile.

I need to test the batteries powering the Model B and the AAXA projector to see how long they last. Note that the projector has its own battery but it only lasts about 90 minutes and can run of power input, so it's likely I'll just run it off the single (or dual) batteries.

#3 Updated by Hammel about 6 years ago

  • % Done changed from 30 to 50

Ordered new micro USB cables for powering devices. I have a set of 5 1' cables and a set of 10 5" cables on order from Amazon.

Also ordered the following alternate batteries and a 4 port power adapter:
  1. Jackery Giant+
  2. Jackery Mini
  3. Pwr+ PowerBlast Power Adapter

That Pwr+ should allow me to recharge any of these batteries pretty fast. The Jackery Giant+ has a 2.1A and a 1A USB connector that should allow me to run both the RPi and the projector long enough to play a movie. The Jackery Mini is similar to the IO Gear twin pack except it was $10 cheaper but for only 1 battery.

#4 Updated by Hammel about 6 years ago

I ran a Media Player on the Jackery Giant+ for several hours, just sitting there (not playing a movie yet), and it didn't drain the battery. I had the projector connected to the Pi but didn't connect it to the battery (forgot to try that). The AAXA projector I have doesn't run off battery so I'm unclear what will happen if I plug in the batter while the projector is running. I'll try that tonight.

The Pwr+ adapter is nice since it plugs in and presents the USB ports perpendicular to the prongs. I can plug in up to four devices with USB A connectors without any problem with spacing, though there are caveats to using this to charge anything that needs 2A or more for fast charging.

I didn't test the Jackery Mini but its functionally the same as the IOMagic Rescue Power bars. Only difference seems to be the former has A and micro connectors on one side while the latter has them on opposite ends (I think - gotta review this when I get home).

#5 Updated by Hammel about 6 years ago

  • % Done changed from 50 to 70

Did another field test over this past weekend. The Jackery Giant+ powered both a Pi and the AAXA LED Pico projector without a USB hub. The UUGear 7 port hub's power connector broke off right before we left so I switched to using a new Pi B+ with a Favi keyboard and two USB media sticks. The USB ports are too close to place two media sticks next to each other, but since there are now four ports, two stacks side-by-side, I was able to offset the sticks in the ports. This won't be a problem later when the Media Server is providing the videos and the Media Player won't need the media sticks anymore.

The result of the test was the Jackery Giant+ played two movies (mostly, we stopped the first near the end cuz we were sleepy) and only lost about 1/3 power based on the LEDs that show available charge on the battery. That's perfect for the Media Player. And the AAXA Jr didn't lose charge even though its battery is only 80 minutes, so the Giant is charging the projector while it plays. The AAXA P2 Jr has a longer battery life but doesn't recharge using a mini-usb connector - it requires a barrel connector. So the LED Pico is now the official projector of choice for the Media Player.

Now I just need to get the USB hub replaced in order to get the Media Server hardware officially defined.

#6 Updated by Hammel about 6 years ago

  • Priority changed from Urgent to Immediate
  • Severity changed from 03 - Medium to 04 - Low

#7 Updated by Hammel about 6 years ago

Two things:

I find I can't get a single point power-on with the Jackery-Giant. I would have three power-on points: The giant, the projector and an external switch to power-on and off the RPi. This isn't going to work. So I decided to drop the Jackery and go with a 2100mAH LiPo battery from SparkFun with a breakout board that can be used for charging. I can tie it to an on-off switch to the RPi and the projector. But the Projector will still need to be turned on. So the projector can be manually plugged into a port on the case that's tied to the battery.

Also, the hub isn't working yet. The first version they sent seemed to work okay but then the microUSB connector for power broke off. I tried to put it back on but it won't hold. The problem was the connector was too tight and pulling on the cable pulls the connector off the board. UUGear agreed and have updated their stock to fix that problem. They sent a second board free of charge. Unfortunately, plugging a port of that board into the power of the RPi causes the latter to reboot continuously. I haven't tried connecting the power pins of the USB board to the RPi GPIO pins yet but will try that next.

For now, moving this to 0.10.0 so I can get 0.9.0 out the door.

#8 Updated by Hammel about 6 years ago

  • Priority changed from Immediate to Urgent
  • Target version changed from 0.9.0 to 0.10.0

#9 Updated by Hammel almost 6 years ago

  • Priority changed from Urgent to Immediate

#10 Updated by Hammel almost 6 years ago

  • Target version changed from 0.10.0 to 0.11.0

#11 Updated by Hammel over 5 years ago

  • Status changed from In Progress to Closed
  • % Done changed from 70 to 100

This issue is still open but will be closed because the first the prototype cases are built and the use of the Jackery Giant are sufficient for now. Integrating single power source for the player will require a custom DLP (projector) board, which is beyond my scope (and talents) at the moment.

Closing issue. I'll open a new issue when/if I ever get to the DLP board design.

Also available in: Atom PDF