I totally agree with you on the retail cost of the parts being WAY lower than the retail cost of finished goods. But the mfger must amortized R&D, warranty replacements, profits,
On the "bricking" of the BMS: Most BMSs are very sensitive to the power-on sequence. If you simply connect the...
I WISH that the bike industry had the "morals" and accountability of the electronics industry. The semi manufacturers know that their customers will sample test and measure the performance of what they paid for. Forced morals and accountability.
YES. Exactly.
Just a small correction: The balancing mechanism is to "switch on" small surface-mounted resistors (with PWM using FETs) to keep the cells that reach 4.20 volts from exceeding that voltage. The current to the whole pack is restricted during this phase by the power limits on...
Chargers with an adjustable endpoint are already available in the aftermarket for 48 and 52-volt packs. It is a very cheap and easy analog solution, but the circuits must be accessible to install an adjustment pot.
These Luna Charger 48V Advanced 300W Ebike Charger also have an adjustable...
This sounds like the BMS is balancing the cell groups, but maybe going too far.
But def a BMS problem and not the charger. Chargers are relatively stupid devices. The BMS is where the "intelligence" is.
Yes, I agree with all you have said. Both packs are likely way out of balance. I suggest several cycles of charging to 100% and discharge to shutdown. If that doesn't work the pack would have to be torn down to expose the balancing wires currently connected to the BMS.
What we should be...
As you said, these loggers are very useful until the battery voltage drops out. At that point, you lose everything.
How do you power the logger from a second battery? Mine runs off of the main battery, as it is in series between the battery and motor controller.
Here's my second post on your problem:
Let's look at the (great) data you collected:
1 - In the first dataset, your pack voltage drops out completely after a relatively short, mild rise in load current (from 4 to 6 amps). The pack voltage droops about 250mV as the load increases and then the...
I agree that your pack could be un-balanced. The way you are charging your batteries could be the issue, combined with the design of these small packs (13S2P).
You said: "I am very diligent about charging them to 80 or 90% if not in use." Only charging the pack to 90% is a great strategy to...
Yes. This is what I do, rotating the packs every two weeks when I charge my Garmin...
And the derailleur likely runs on typical Li-Ion 3.7 volts nominal. To have a central power source you would need a DC to DC converter.
The BMS would be exactly the same. BMS's monitor only the parallel groups, not each cell in a parallel group.
A 10S1P battery has the same number of monitoring "wires" as a 10S2P pack.
Just googled that and see the ownership change. Thanks for the news...
The article said that Spec and Trek both offered to buy them. And that Trek is buying many large cycling retailers in the US.
What changes are next?
My local Specialized dealer is Mike's Bikes. They are the largest chain of bike stores in Northern California with twelve large stores between San Jose and Sacramento. They carried Specialized, Santa Cruz, Orbea, Cannondale, BMC, Giant, Salsa, and twelve other brands.
They have just now...
Schwalbe Rocket Rons with the Speed Addix compound are the fastest rolling tires I've found. They are also lighter than most any tire you can find in a comparable sidewall durability class.
I use the Snakeskin sidewall, which is a compromise between durability and weight. There is another...
Great photos that show your commitment and capabilities!!
But what are these motors marked "45km/h"?
Are they tested at that speed? Are they unrestricted to that speed?
I thought the speed limits are in the firmware...
I have a 2016 Alloy Turbo Levo, and I am fed up with the ridiculous POS Command Post, which never worked from the start. I want to upgrade to a Rockshox Reverb Stealth with, of course, the same 34.9mm diameter. Who has done this upgrade on their alloy Levo?
My question: What is the...