expresso wrote:BM - on a chair thats 6.5mph - stock - if adding tires 350-8 and lithium - adding volts to the motors - from a stock 22.5V to 25.5V - or 25V - would 8 or 8.5mph be reachable ?
steves1977uk wrote:Never had those issues in W10, mind you I strip out most of the unwanted garbage before I install it. Now I run W10 Ent LTSC2019 with the Store apps I CHOOSE to install, best of both worlds!
Steve
shirley_hkg wrote:Yes. Shirley has bunch of them to offer.
Burgerman wrote:But for the life of me I cant see what possible pleasure anyone would get out of doing that.
terry2 wrote:expresso wrote:BM - on a chair thats 6.5mph - stock - if adding tires 350-8 and lithium - adding volts to the motors - from a stock 22.5V to 25.5V - or 25V - would 8 or 8.5mph be reachable ?
Wouldn't adding volts damage the motors?
My 8mph motors does 8.4 on a flat.
If it was safe, I would up the voltage as well.
expresso wrote:terry2 wrote:Wouldn't adding volts damage the motors?
My 8mph motors does 8.4 on a flat.
If it was safe, I would up the voltage as well.
you can maybe gain at least 9pmh with a few extra volts - once you try it - you may not want to go back
LROBBINS wrote:Clearly that device is unsuitable, but I do wish someone could find a cell balancing board that would: (1) start balance only near or at the end of CV, (2) dissipate or exchange enough current to balance reasonably quickly (would 3A be enough?). It should be rugged enough to be mounted in the chair and not need any user attention (after initial programming). As it would only be doing something when connected to a charger, it can be a passive balancer that just dissipates energy from the highest cell - the mains watt-hours wasted would be tiny in any case.
There are lots of cell monitor/balancer boards out there that use an Analog Devices or TI chip that can do the above, but that can pass only mA of current. One of those chips plus 8 MOSFETs and 8 resistors would seem to be all that we really need, but I'm not up to designing and testing same (at least not with too many other projects underway). So, with all the "stuff" that's out there, isn't someone making a simple board like this?
The only thing that has kept me from going LiFePO4 has been the fact that we can't have a setup that only I can hook up for charging. It's hard enough to get people to remember to push the rocker switch on her dumb charger (and even I have forgotten once in a while), no less follow a sequence of who connects to whom followed by one or more button presses. It's not just that I'd rather not have yet another daily chore. Perhaps if I were 40 or 50 y.o. that would be OK, but I've already got 73 behind me and Rachi is going to still need her chair well after I'm gone.
Clearly that device is unsuitable, but I do wish someone could find a cell balancing board that would: (1) start balance only near or at the end of CV, (2) dissipate or exchange enough current to balance reasonably quickly (would 3A be enough?).
No John, that's not what I have in mind. I would want the balance board to not do anything until near or at the end of CV when it would then tell the power supply to reduce maximum current to what the balance circuit can handle and only then start to dump from the highest cell. In other words, there would be no involvement of the balancing circuit except at the "finishing" stage.
LROBBINS wrote:I am avidly awaiting news of this. Not that I need another project, but it's absolutely clear that the next battery for Rachi's chair WILL be LiFePO4 - even if a balancer for dummies does not become available.
expresso wrote:terry2 wrote:expresso wrote:BM - on a chair thats 6.5mph - stock - if adding tires 350-8 and lithium - adding volts to the motors - from a stock 22.5V to 25.5V - or 25V - would 8 or 8.5mph be reachable ?
Wouldn't adding volts damage the motors?
My 8mph motors does 8.4 on a flat.
If it was safe, I would up the voltage as well.
only way to know for sure is to do it and hopefully it wont damage them - it may shorten its life a bit i would think - i guess it depends on the motors - how well built they are in the first place etc,
stock volts are keep lower because of lead - most likely - since lead cant supply more - but lithium can and does stay steady at 26v till it at its end - so we can make use of higher volts 24v 25v etc, leaving a little left over for control - gaining free speed and not loosing bottom end either -
you can maybe gain at least 9pmh with a few extra volts - once you try it - you may not want to go back
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