How about this?
get the one i linked first, i should think it will keep you going for several hours. If its not enough just by another and run in parallel. Or you could (don’t do this) just buy 4 and run them all in parallel. then you would have the same 20ah at £100 less than the one you linked.
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Thank you for sharing you knowledge with me. Will be making an order soon & I hope it will resolve the issue with my rover not having the ability to turn 360*
You are likely to have trouble with the compass with those modules on the deck right over the motors. A couple of modules stands would be a good idea.
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Yes that’s true, I will be elevating them with some stands soon but since I had the issue with the rover not turning I didn’t add any mods to the rest of the vehicle. With my old rover once I elevated the compass/gps modules that’s how I got those nice offsets👍🏼
That is a nice clean looking installation, good job. I’ll be interested to see how it performs. I agree a couple 3S 5000-8000mah batteries in parallel will be the best option. Based on current draw on my Rover the 6400mah battery I use should run the truck at Mission speed (~1m/s) for a couple hrs. I had it running a loop around the house to test this but due to small positional errors it would run into deep snow, wheel spin and switch to Hold mode. That feature actually works quite well.
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Thank you Dave, I tried to make it look as neat as possible. I’ve ordered the following battery:
20000mAh 3S2P 11.1v 20C Lipo Battery - Overlander SupersportXL
This Lipo fully charged comes to around 12.6V so I’m hoping the additional .6v won’t cause a fire🙏🏼
This way I can save on space and get 20000mAh worth of runtime at the required voltage.
On a side not regarding “save parameters”
I saved the parameters that worked & I then changed a few. After I made the changes I loaded the old saved parameter file and it didn’t go back to the original parameters. Not sure why
Oh well. I would have gone with a couple of smaller batteries. Carry what you need and less of a problem to keep at a storage charge when they are not being used.
That’s what I was going to say. Properly managing large capacity batteries is a PITA even if you have a a good way to discharge them. You could have bought a couple of 8Ah 3S’s for ~$50 ea and had more flexibility.
Ya. I have 6 of the RMRC 8000 mAH batteries. I think they have discontinued them though. I charge what I need and only what I need.
That battery weighs almost 1.2kg. If you add more weight, turning will get harder and wear on all moving components will go up.
And charging that beast will take ages.
Using multiple smaller batteries in parallel is the better way most of the time. You can keep the rover powered while you change batteries and you can decide if you want to run the rover light or heavy.
The price also goes up as the individual cells get bigger.
Looks like it has already been ordered. Live and learn.
I think it’s ill advised to load that vehicle down with the weight of that battery as Sebastian suggests. All the load is on the motor shafts and those Spur gear motors probably have bushings. The Planetary gear motors I previously suggested have ball bearings and could take it. And Wow, a $224 battery.
I used a 4S lipo battery I had spare last night that’s 14.8v 1300mAh & the rover turned round 360* a few times then the power depleted very quickly. I mean in a matter of a minute it wasn’t turning on the spot anymore. The battery doesn’t weigh hardly anything so maybe there’s another issue with the rover
1300mAh is a small battery and turning on the spot requires a lot of power with a 4WD rover, even more on soft surfaces like carpet. So it may very well be that the lipo depleted so fast. You should also listen to what the others said about overvolting brushed motors. With a full 4s lipo you are at 16.8V, that is 40 percent over the rated voltage. The brushes are going to burn down very quickly if you keep overvolting the motors.
So is the power coming from the voltage or the amps of the battery Or both?
Because last night 14.8v “which is plenty” for this rover didn’t get the rover turning for more than a minute.
And 1300mAh didn’t do the trick either. So I’m not sure why the battery I used last night only had little effect in improvement. A minute of improvement to be exact.
The battery I used last night should have been sufficient enough no?
What is the C rating of the battery? If you use a power module you would be able to see in the logs, and in real time on mission planner, the Amps you are pulling and the voltage
This is the battery I tried last night which lasted a minute & made the rover make a few 360* turns:
Specifications:
- Capacity: 1300mAh
- Voltage: 14.8V
- Max Continuous Discharge: 75C
- Max Burst Discharge: 150C
- Weight: 146g ±10g
- Dimensions: 703530 mm ±5mm
- Balance Plug: JST-XH
- Discharge Plug: XT-60
- Charge Rate: 1-3C Recommended, 5C Max
The info on the battery I will be trying once it’s delibered:
Max continuous discharge for the tattu lipo says 75C, the bigger battery says 20C
This is the battery that is on the Lynxmotion Webiste which they recommend for the rover I have purchased:
- Nominal Voltage: 12V
- Chemistry: NiMH
- Capacity: 2.8 Ah
- Continuous Discharge: 2.8 A
- Burst Discharge: 5.6 A
- Connector: Tamiya
- Cell Type: Sub-C (10 Cells)
both, power is current times voltage, watts = amps x volts
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