1. Do not share user accounts! Any account that is shared by another person will be blocked and closed. This means: we will close not only the account that is shared, but also the main account of the user who uses another person's account. We have the ability to detect account sharing, so please do not try to cheat the system. This action will take place on 04/18/2023. Read all forum rules.
    Dismiss Notice
  2. For downloading SimTools plugins you need a Download Package. Get it with virtual coins that you receive for forum activity or Buy Download Package - We have a zero Spam tolerance so read our forum rules first.

    Buy Now a Download Plan!
  3. Do not try to cheat our system and do not post an unnecessary amount of useless posts only to earn credits here. We have a zero spam tolerance policy and this will cause a ban of your user account. Otherwise we wish you a pleasant stay here! Read the forum rules
  4. We have a few rules which you need to read and accept before posting anything here! Following these rules will keep the forum clean and your stay pleasant. Do not follow these rules can lead to permanent exclusion from this website: Read the forum rules.
    Are you a company? Read our company rules

Extra Power For Thirsty Motion Rigs

Discussion in 'Electronic and hardware generally' started by Zed, Jan 17, 2022.

  1. Zed

    Zed VR Simming w/Reverb Gold Contributor

    Joined:
    Apr 4, 2017
    Messages:
    1,044
    Location:
    USA
    Balance:
    5,828Coins
    Ratings:
    +1,042 / 4 / -0
    My Motion Simulator:
    2DOF, DC motor, JRK
    Between my 2DOF and computer system, I’ve stretched the circuit feeding my office about as far as I dare. I have wanted to build a 6DOF but power requirements stopped me cold. Others have done things like install batteries and chargers to get more juice, and many have located rigs near breaker panels to get what they needed. Those aren’t options for me.

    There have been some battery advances and a whole new line of products has recently become available that get my rig around the power issue. They are portable and self-contained backup power units. They are like portable generators but no gas and they are quiet, clean, and smart. Expensive too, but it may be easy to justify as an emergency power source as power grids seem to be seeing more weather outages. They are also expandable. You can increase power storage and delivery by adding battery modules or additional entire units.

    The units are about ice chest sized, use LiFePO4 batteries (much safer than the more common Li-ion-Co batteries), and support multiple charging methods and outlet styles. The thing about the lithium iron phosphate batteries is they don’t mind lots of charge/discharge cycles without losing much capacity. They are fine with daily full charge/discharge cycles for up to 15 years without much capacity loss. Depending on the unit, they can charge directly from solar panels, a wall outlet, or even EV charge stations.

    Li-Co batteries commonly used in electric vehicles and things like Tesla Power Wall units swell and shrink a lot with charge state. That damages the batteries internally with every charge and discharge cycle and can make them prone to failure if there are any manufacturing defects lurking. They have slightly higher energy density than LiFePO4 but limited lifetime with lots of charge/discharge cycles. LiFePO4 internal battery components are virtually the same size in charged and discharged states so don’t flex the battery components the same way Li-Co batteries do. (Some EVs are moving to LiFePO4 batteries now because range (capacity) doesn’t drop off for years even with lots of cycles on the batteries - important for those who want lots of cycles and don’t care as much about maximum range.)

    The companies I’m aware of for these portable power units are below but there are probably others. Again, pricey for just being a power source for computers or a rig, but with added utility of being an emergency or camping portable power source, it maybe gets easier to justify.

    https://ecoflow.com/

    https://www.bluettipower.com/

    Anyway, finally pulled the trigger on a unit for myself for backup power as well as seeing how it runs my rig. Will report back once I get it in service.
    • Informative Informative x 1
  2. noorbeast

    noorbeast VR Tassie Devil Staff Member Moderator Race Director

    Joined:
    Jul 13, 2014
    Messages:
    20,463
    Occupation:
    Innovative tech specialist for NGOs
    Location:
    St Helens, Tasmania, Australia
    Balance:
    144,614Coins
    Ratings:
    +10,741 / 52 / -2
    My Motion Simulator:
    3DOF, DC motor, JRK
    Interesting idea @Zed. I suspect in some parts of the world people will go down that path for different reasons, for example in parts of Australia the take up of roof solar is so high it makes the grid unstable.

    Out of curiosity have you investigated the fire risk? The likes of Tesla, in cars and even in large commercial storage units, are famous for fire intensity should they ever burn.
    Last edited: Jan 18, 2022
  3. Zed

    Zed VR Simming w/Reverb Gold Contributor

    Joined:
    Apr 4, 2017
    Messages:
    1,044
    Location:
    USA
    Balance:
    5,828Coins
    Ratings:
    +1,042 / 4 / -0
    My Motion Simulator:
    2DOF, DC motor, JRK
    Good question and I have investigated fire risk. These units use lithium iron phosphate batteries which are very different from the lithium cobalt batteries in most EVs and much safer. The way batteries work is a chemical reaction so you have one set of chemicals and materials that gradually converts to another set of chemicals and materials as the battery charges or discharges. In the lithium cobalt batteries used in most EV cars, the charged and discharged forms have a significant size difference. Each cycle flexes the battery components a bit.

    In the lithium iron phosphate batteries the charged and discharged sizes of the battery internals is almost the same so much less mechanical issues in the battery. The chemistry is also much more stable. Some materials in the LiCo batteries are flammable on top of the energy dump when the batteries get punctured or crushed. LiFePO4 batteries are slightly less energy dense and a little heavier, though. For a given battery volume you get less stored energy and it weighs more but you can cycle them many many more times before significant degradation. Up to 15 years of daily full cycles to 50% capacity. 10 years to 80%.

    But Tesla is also moving to LiFePO4 for some vehicles. They are good for frequent charge/discharge applications instead of highest mileage. But these small UPS/backup unit families are both LiFePO4 at least the units I’ve looked at.

    Sandia National Laboratory has a well-known battery lab where they look at all sorts of things about batteries. They looked into battery safety differences between LiFePO4 (referred to as LFP) and LiCo batteries. When the cells short internally, the LiFePO4 batteries heat at lower and safer rates which tend to not result in fires. Interesting failure data here: https://www.osti.gov/servlets/purl/1336278 (Use the View Conference button)

    Also, about the power grid instability, the newer solar systems, especially those with battery backup, now have features to help stabilize the grid. Either automated or controlled by the utility. They can put more voltage on the grid when voltage sags and help pull or push the peaks. IIRC both Hawaii and California mandate new installs to support those features. These features will probably be required in more areas but most new equipment already meets the new requirements.

    https://www.hawaiianelectric.com/pr...olar/customer-energy-resource-(cer)-equipment
    Last edited: Jan 19, 2022