Battery Bro recently supplied Molicel Battery into the Mars Rover Design Team in Missouri S&T.
We’re fascinated by space, and also the watch lithium-ion as an”enabling technology” that will help us achieve the world’s spacefaring targets.
Therefore, we requested the design team to get a meeting that they had been pleased to oblige!
We talked with Alyssa who answered each the questions under on behalf of her staff.
Let us talk to Alyssa
Chief Executive Officer
1. What’s the point of your job?
The Mars Rover Design Team is a student run layout group situated at the Missouri University of Science and Technology (Missouri S&T) at Rolla, MO.. The objective of the contest is to design and construct up the”next generation” of Mars Rovers, which will one day work together with people in the specialty. The group competes annually at the University Rover Challenge (URC), an global contest held in Hanksville, Utah. The group was competing for three decades. In 2015, we became the first American group to compete at the European Rover Challenge, held in Kielce, Poland. The team placed 10th out of 44 teams from all over the globe! Learn More here:
2. Why did you select LG INR18650HE2 lithium-ion cells to your own project?
We picked these cells Because of Their high current output and Superb value
The habit ion package configuration used from the rover
3. What type of pack configuration do you use for the cells, and why?
We’ve got the cells configured in eight modules in series, with every module home 10 cells in parallel. We use this setup to attain our desired output of 33.6 liter in no more than 200 amps.
4. What type of temperature extremes would be the rover encounter, and how are you going to control ?
While the rover won’t really go to distance, the hills of Utah may have some fairly intense heat. We’re thinking about implementing a cooling system with enthusiasts to stop the batteries from overheating, and will be carefully tracking the temperature of the batteries involving jobs.
5. Are there any other risks to your own battery system introduced by the extreme environment in distance?
If the rover go to distance, there would need to be a few radiation-protection shell covering the tissues, protecting the cells and the rover from some other intense environments it might encounter. To be able to save cost, the contest doesn’t need us to look for the true feeling of Mars.
6. How can you regulate the battery output (e.g. BMS), and just how can this must be corrected for distance?
The battery output has been controlled through our custom made battery control system, which tracks the voltage of each module in addition to the present output in the package. The output is controlled further at our custom made electricity board, which measures the package’s voltage again and monitors voltage and current outputs. Whenever these presses act unexpectedly, these systems are programmed to turn off voltage busses or detach the bunch completely in the rover. Again, the contest doesn’t need us to look for distance requirements, saving us both money and time.
The battery variety is going to be a long, flat surface which will slip underneath the rover, rather than the cube-like range from this past year. Leaner & Quicker is among the key topics this season.
7. Are there any special or unusual facets of your package design (form variable, tabbing, etc.)?
To join the cells in parallel to create our modules, tabbing is spot-welded round the cells’ terminals. To link these modules together in string, habit 3D-printed moldings are utilized and screwed together. Additionally, the batteries have been put at a pallet-like configuration, like the manner Telsa battery cells have been laid out. This lowers the middle of gravity, and also allows for physical separation between battery terminals. Very similar to Teslas, this setup needs us to design and construct a slide plate to the base of the rover.
8. What’s the planned recharge / utilize program for those batteries?
A. Do they closed down throughout the Mars nighttime?
b. Should they recharge throughout the Mars day, just how long can a complete charge take?
This season, the BMS also costs our batteriesso we won’t require an external charger. They’ll be billed between competition activities and at night. A 90% fee should take about 2-3 hours, also varying time for trickle charging.
If you’re interested in knowing more about distance batteries, a .PDF printed by NASA branded Guidelines for Lithium-ion Battery Use in Space Applications (54 pages) will be the perfect place to get started.
Current space batteries
Curiosity, Spirit, and Opportunity use lithium-ion batteries made by Yardney.
Yardney batteries boast the following attributes:
Outstanding energy density — 358Wh/L
Excellent particular energy — 145Wh/Kg
Long operating life — 2100 deep cycles
Impressive discharge capacity
Continuous 10C speed
Pulse 50C speed
Rapid recharge capacity — C speed
Broad temperature capacity
-40° C to +65° C
True prismatic layout
As you can see, an integral differentiator is that the temperature that the cells can deal with. Typical 18650 batteries aren’t able to perform under 20 degrees Celsius. This really is a great goal for mobile creation.
1 such battery chemistry employs internal immunity to make self-heating cells (Link: Nature) that will conserve energy (reduce mobile degradation and alleviate less environmental warming ).