It would be very helpful to add the ability for the user to set a charge limit. Even with daily usage the yarbo is still sitting idle on the docking station with the battery at 100% SOC. Long periods of time at very high or very low SOC causes significantly accelerates capacity degradation in NCM Li-ion batteries. This is even worse as it sits outside in the heat all day.
Not charging regularly above 70%-80% would significantly extend battery longevity. Also, in the future it may be useful to switch from NCM chemistry to LiFePo4 which is much more tolerant to the use case for the yarbo.
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Thank you for your suggestion! We understand your concern about the battery health, and we do have a battery management system in place to help maintain its longevity. We also appreciate your feedback on the charge limit feature to further extend the battery lifespan, and we will pass this on to the relevant department for consideration.
Regarding the battery chemistry, NCM is chosen for its ability to provide relatively longer range, which is an important factor for the performance of Yarbo. However, we are always open to exploring improvements and will keep your suggestion in mind for the future.
Thanks again for your input!
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I love the feature of being able to return to the charger at user specified (default at 20) percent of charge.
The question is what is 100% of charge in Yarbo, what voltage? If 4.200 or above, it’s probably too high to let the battery sit for long periods, or for that matter, even overnight. If it’s less that 4.200, then maybe 100% is more like 90 or 95%…
So just asking for either a user adjustment on 100% charge, or a bit of factory-provided headroom at the top to maintain the battery a much longer lifetime of 80-90%.
Most of my jobs can be done with about 50% of charge, so I don’t need all the watt-hrs the battery can store. Not everyone has that situation, understand but for those of us that do, but please give us longer battery life over longer run time between charges …pretty please.
Tim
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Just one more comment on this most excellent product improvement idea…I’ve been told by Yarbo Support that the BMS is similar to modern cell phones and computers, and that it takes good care of the battery, even at 100% charge. I think that is the problem right there…because those devices are usually optimized for long run times, not long battery life. Which is fine maybe, if you are cutting 3,4,5,6 acres, or more, that might be what you need. For a lot of us (I’m at 1.2 acres pasture land) we would rather have the BMS act more like a modern EV, where the user gets to decide on priority, long life or long run time. You could just add the adjust top end (say 70-100%) in the same place you let the user set the low end (defaults to 20%), for this improvement.
Thanks for having a place to spell this out! And for having an awesome product!
Tim
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Point of order:
Don’t forget that the BMC needs to balance the cells on occasion, or else hilarity will ensue. These are not 2S cellphone / laptop batteries.
Cheers
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If my math is right (feel free to check), the cells are probably getting balanced every charge. Most BMS are set to balance at some cell voltage over nominal. For NCM lithium, they have a nominal VDC of 3.6V per cell. The Yarbo specified nominal battery pack voltage for Yarbo is 36V, so that means this is a 10S or 10 cells in series pack. Both of the chargers (wired and inductive) are specified in the specifications for 42V, which would be 4.2Vpc (if it’s a 10S pack). It would not be good if the cells are not balanced or being balanced at this point. It’s also not great if the cells are being held at 4.2V for long periods of time, like overnight. I would be very happy with an adjustment on the top end like we have on the bottom end, with the default at 20%.
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