Endless Sphere

Normal in my view. Close to 3.0 to 3.2 volts, a very small capacity usage cause huge drop in voltage. This is not nearly the case when you are closer to nominal (3.6-3.7V) voltage where capacity usage cause only small variation in voltage. So cell voltages will be much closer togoether when you rech...

If you can unplug the BMS, store at 20-30%.
Otherwise, store at 30-50% and monitor voltage of cell groups every 6 months and balance as required.

Starting 60% and higher, cell degradation will go faster. Temperature is also key. I'd store at 10°C if possible.

Matador

I'd go with triangle pack for off road. 1) you can attach ot to 3 metal tube, so it can't sustain more lateral G-force than a shark pack held by two waterbottle holes (warning, flying battery pack ahead). 2) You can put way more cells inside (14S10P ??) so you got more capacity, better suited to cop...

Anyway, the bike is cheap but works and the battery, hub and controller are rather inconspicuous, so "sort of stealthy". [...] Here's my question :]How much can I safely overclock the system and how would you do it ?] Switch to a 48V or 52V battery. That will adversely impact your stealth...

A 14S4P pack made of GA cells (max 8A/cell) is rated for a max of 32 amps current. Using at 50A (12.5A/cell) would likely damage the cells inside the pack.

I would first check the voltage of each cell groups. Make sure all are sitting at the same voltage. If not, balance charge every cell group to the same voltage. The Ancheer battery actually is not equipped with a balancing BMS (just a dumb protective PCB for low voltage cutoff, hig voltage cutoff an...

Cooling the motor doesn't make the motor loose less energy in heat, it just hides the fact that the motor is loosing the same amount of heat. Overheating can 1) Demagnetize the neodynium magnets of a BLDC 2) Melt the winding. P=RxI², meaning if you double current, the power loss in heat quadruples. ...

Cooling the motor just sheds the heat you are making quicker, it does not in and of itself make it "better". However, a hot motor does run less efficiently, so preventing extreme heat build-up is a good thing. If the heat build-up is not extreme, then no real need for extra cooling. Total...

You can also just use a 12V server power supply with an adjustable digital boost converter like the MingHe BST900W. The adjustable digital boost converter allows you to choose a charge voltage anywhere between 10V and 120V. Very versatile and cheap. Search the forum for "MingHe BST900". Th...

Thats a beauty! The framebox is absolutely stunning (i'm a bit jealous) I'd love to see pictures of the framebox byulding process.

Matador

But ultimately, what I'm saying is: Sure it's possible that corrosion between the cell terminals and the steel strips eventually develops. And sure that corrosion could add a bit of resistance to the current path and create a bit more heat. But the real immediate problem is the intrinseque resistanc...

so is this exact Any venting that a cell can potentially do will corrode the steel under the nickel plating. Any fingerprints will corrode the steel under the nickel plating. After corrosion starts, heat builds up in the area and more corrosion starts until it burns through. ? I was refering to you...

want to build wrote: ↑

Sep 20 2020 9:51pm

Matador wrote: ↑

Sep 20 2020 9:34pm

If we are at the point of talking about cells venting or leaking electrolyte, then you got bigger problems to worry about than your metal strips.

what do you mean by this comment . where does cell venting or leaking electrolyte comes from in this post?

Exactly.

If we are at the point of talking about cells venting or leaking electrolyte, then you got bigger problems to worry about than your metal strips.

Heat will be generated from the non-correded but intrinsequely high resistance nature of steel strips. Poor conductivity of this type of metal yeilds to metal turning red hot (heat) when current is past through them. P = R x I² (Ohms law), where P is the power (in watts) dissipated as HEAT by the me...

Reversed heatsink mod.
[youtube]g-ZIlVZWA2s[/youtube]

It's bolted on the motor, just like the stock one.

Matador

I have several BST900 (2 in my solar shed to charge ebike batteries, another one to transfer energy in a more open way) I noticed only 1 had the IXYS part, the other two were the inferior Fairchild reference. I managed to bulk charge one of my batteries at 6Amp, the input current was like 12amp, an...

I just came across an updated video from Justin at Grin concerning the Grinspector battery testor.
Nice updates to the software. Can plot DCIR against SoC. Awesome!

[youtube]Ogv772eM-EU[/youtube]

Matador

If you mean nickel plated steel, the real problem is actually the very poor conductivity of nickel-plated steel compared to pure bare nickel metal. Carbon steel (1010) is less than halve than the conductivity of nickel. Stainless steel is a tenth of the conductivity of nickel. Nickel is already not ...

Got an old Bafang BBSHD (running 30A at 58.8V). Bought in in August 2016 IIRC. I don't use the Hailong case for my 52V battery. Should I be concerned and rebuilt for 48V (buying new BMS, charger etc)??? Or can I just carry on at 52V? I mean, Luna Cycle was pushing 50A at 58.8V with their "Ludac...

ES-MeridianAfter.jpg This is my mother's trike Schiwnn Meridian bought it for $200 new. She had balance issues also, had to give up her bicycle. I added Bafang G311 (front, no traction issues) and grin's 20a Grinfineon controller, CA3, PAS and thumb throttle. Moved the basket back couple inches and...

That fat trike looks fun! Here's how mine looks... resize.jpg KIMG0387.jpg KIMG0367.jpg The second picture is after putting it in party mode lol. This particular one, the diff is incredibly beefy. Check out the size of motor chain compared to the prefer chain... It's big. Looks quite comfy ! Seat l...

Just saw an awsome old video to understand how a differential works:
[youtube]yYAw79386WI[/youtube]

I saw this on youtube (BBSHD on a Manhattan trike) but the owner seems to say it's a solid rear axle which doesn't seem to make sense since it turn on a dime without the wheels rubbing... It’s one wheel drive, like almost all granny trikes. Some of them use half axles and only drive one side, while...