Search found 6106 matches

by john61ct
Apr 05 2021 11:42am
Forum: Alternative Energy
Topic: Running a house on an e-motorcycle battery?
Replies: 63
Views: 1266

Re: Running a house on an e-motorcycle battery?

That's a bit too strong, overstated IMO but yes, this use case is not motivated by too many practical benefits. But getting off the grid completely is IMO a fine goal if you can afford it. I lived that way for decades, but in a place where just connecting to utilities would have cost more than the l...
by john61ct
Apr 05 2021 9:04am
Forum: EScooters/EMotorcycles
Topic: how to program a sevcon gen4
Replies: 334
Views: 94048

Re: how to program a sevcon gen4

In my experience asking dealers, they only supply the software and license to paying customers, either buying the hardware or retaining them on an annual service contract. My impression was the goal is to reduce the value of secondhand units in circulation. I don't understand why there aren't freela...
by john61ct
Apr 05 2021 2:11am
Forum: EBike Technical
Topic: BMS destroyed my battery?!
Replies: 51
Views: 1060

Re: BMS destroyed my battery?!

if they had a bluetooth bms like the Ant bms you could set the lvc at 2.5v program balancing to start at 2.8v I've never heard of a protective BMS that bottom balances. Only dedicated balancers ( marketed as "non-protective BMS") or node charging can middle or bottom balance afaik > i thi...
by john61ct
Apr 05 2021 2:01am
Forum: EBike Technical
Topic: BMS destroyed my battery?!
Replies: 51
Views: 1060

Re: BMS destroyed my battery?!

if you top-balance at 4.2V and discharge to 4.1V, the cells will necessarily be closer than if you top-balance at 4.1V and discharge to 4.0V. Not practically relevant, just refuting the claim that top-balancing at 4.2V would "throw the pack out of balance" But it does do that! In my case ...
by john61ct
Apr 05 2021 1:18am
Forum: EBike Technical
Topic: [SOLVED] Balance Discharger... or is there anything else?
Replies: 43
Views: 1293

Re: Balance Discharger... or is there anything else?

Node chargers are a different category, maybe you don't think they are useful in general but if you want to say it is a bad node charger, then specify those that are better please. It puts out a pulsed current in order to measure the "reverse bounceback" delta, kind og like getting a bead ...
by john61ct
Apr 04 2021 2:08pm
Forum: Alternative Energy
Topic: Running a house on an e-motorcycle battery?
Replies: 63
Views: 1266

Re: Running a house on an e-motorcycle battery?

A smart charger seems to be a possible answer, as that will be the way to keep the solar power and the grid power seperate with energy only flowing in one direction. I wonder how much a charger would cost that can provide a 48v 40amp charge and be able to turn on and off automatically at predefined...
by john61ct
Apr 04 2021 1:58pm
Forum: Alternative Energy
Topic: Running a house on an e-motorcycle battery?
Replies: 63
Views: 1266

Re: Running a house on an e-motorcycle battery?

Yes of course if you have grid power available anytime on demand

and doing so does not violate your goals

then just a couple of dirt cheap FLA GCs will do, and keep the moto side simple and separate at 96V


by john61ct
Apr 03 2021 11:12pm
Forum: EBike Technical
Topic: BMS destroyed my battery?!
Replies: 51
Views: 1060

Re: BMS destroyed my battery?!


goatman wrote:still waiting for someone to tell me the right term :D
It's your baby, you name it.
by john61ct
Apr 03 2021 11:11pm
Forum: EBike Technical
Topic: BMS destroyed my battery?!
Replies: 51
Views: 1060

Re: BMS destroyed my battery?!

Balancing with unmatched cells is inherently temporary. It doesn't matter if you top balance at 4.1 or 4.2V, or bottom balance at 3.0V -- the pack will only be balanced at the voltage you balanced it at, and necessarily must be unbalanced everywhere else. Truth, and another one many do not grok > I...
by john61ct
Apr 03 2021 11:00pm
Forum: EBike Technical
Topic: BMS destroyed my battery?!
Replies: 51
Views: 1060

Re: BMS destroyed my battery?!

Well, it would be balanced at 4.1V/cell -- but otherwise just as unbalanced everywhere else. Charging under max is for cycle life, not balance. For those doing top balancing, most use BMS that only **start** balancing at a too-high voltage and have a very very slow / low mA balancing current and of...
by john61ct
Apr 03 2021 10:56pm
Forum: EBike Technical
Topic: BMS destroyed my battery?!
Replies: 51
Views: 1060

Re: BMS destroyed my battery?!


fatty wrote:You know lithium ion batteries don't have sulfur in them, right?
He just (mis)uses the term for some protocol to help "resuscitate" old worn cells.

Has a whole thread with that in the title, and yes he has acknowledged it's an improper use of the term

by john61ct
Apr 03 2021 10:54pm
Forum: EBike Technical
Topic: BMS destroyed my battery?!
Replies: 51
Views: 1060

Re: BMS destroyed my battery?!


fatty wrote: not likely to contribute to BMS failure.
Instances of most BMS models just fail, they are usually the weakest link and live up to Battery Murdering System

No reason to look outside their own build quality for failure reasons

by john61ct
Apr 03 2021 8:20pm
Forum: EBike Technical
Topic: [SOLVED] Balance Discharger... or is there anything else?
Replies: 43
Views: 1293

Re: Balance Discharger... or is there anything else?

Discontinued, haven't seen any for years.

by john61ct
Apr 03 2021 7:54pm
Forum: Battery Technology
Topic: Voltage at Discharge Port
Replies: 2
Views: 112

Re: Voltage at Discharge Port

2 categories of BMS, single port design, vs

dual, separate port for charging

by john61ct
Apr 03 2021 7:51pm
Forum: Alternative Energy
Topic: Running a house on an e-motorcycle battery?
Replies: 63
Views: 1266

Re: Running a house on an e-motorcycle battery?

Again, I understand your intention about the batteries

I am just maintaining that the battery suitable for the moto will be too small for the house.

Or, the battery you will need for the house, will be too big and heavy for a moto.
by john61ct
Apr 03 2021 7:39pm
Forum: EBike Technical
Topic: BMS destroyed my battery?!
Replies: 51
Views: 1060

Re: BMS destroyed my battery?!

Doubtful: area under curve during constant current between 4.1-4.2V is minimal, and some BMSs need to be held at 4.2V to balance. Never buy such a stupid BMS, or at least avoid using it for balancing packs where doing so takes more than a few minutes. Your tools should suit **your** care parameters...
by john61ct
Apr 03 2021 7:28pm
Forum: EBike Technical
Topic: BMS destroyed my battery?!
Replies: 51
Views: 1060

Re: BMS destroyed my battery?!

I think that the high voltage cutoff in the bms should still come into play in some cases even when charge voltage is set correctly: example: let's image a really badly balanced pack, let's say 19 of the twenty parallel groups are at 3.5 volts and 1 out of twenty is at 3 volt. You should be regular...
by john61ct
Apr 02 2021 10:50pm
Forum: Alternative Energy
Topic: Running a house on an e-motorcycle battery?
Replies: 63
Views: 1266

Re: Running a house on an e-motorcycle battery?

If there is metered water, even if it's "included" in the rent, the landlord will crack down fast
by john61ct
Apr 02 2021 9:50pm
Forum: EBike Technical
Topic: Compact 400-500A Fuses
Replies: 4
Views: 211

Re: Compact 400-500A Fuses

I'd bet with a quality maker like Cooper-Bussman (Eaton), that 80V has some cushion built in




by john61ct
Apr 02 2021 9:29pm
Forum: EBike General Discussion
Topic: New cycle analyst
Replies: 3
Views: 275

Re: New cycle analyst

There have been threads about both using it in headless mode, and integrating the data stream with Arduino, which would allow you to do anything you have the skillz for
by john61ct
Apr 02 2021 9:26pm
Forum: Battery Technology
Topic: Why does my battery cut out at 51.5 V
Replies: 94
Views: 1985

Re: Why does my battery cut out at 51.5 V

I thought you were taking that BMS out of service?

Adjustable on a good one, but every one is different?
by john61ct
Apr 02 2021 5:16pm
Forum: Alternative Energy
Topic: Running a house on an e-motorcycle battery?
Replies: 63
Views: 1266

Re: Running a house on an e-motorcycle battery?

48Vnominal is fine for a slow scooter, maybe at the high end for House bank usage, but such SCs and inverters do exist, and 48V can pretty easily buck convert to 12V or 24V. And yes, 2S x 48V modules will power a fast bike at 96V, but the BMS if you want one will be the big challenge there. A bunch ...
by john61ct
Apr 02 2021 4:36pm
Forum: Battery Technology
Topic: Why does my battery cut out at 51.5 V
Replies: 94
Views: 1985

Re: Why does my battery cut out at 51.5 V

Again, voltage means zero wrt State of Health

test for capacity, under 80% is nearing EoL

getting below 70% I call scrap, ready for recycling
by john61ct
Apr 01 2021 9:04pm
Forum: Alternative Energy
Topic: Running a house on an e-motorcycle battery?
Replies: 63
Views: 1266

Re: Running a house on an e-motorcycle battery?

OK, sounds like you know more than it seemed at first. Just know that batteries are not optional, the minimum that makes sense just as an overnight buffer would be 1kWh per 500W panel, and double that is still a very low ratio not enough for a few cloudy days in a row. Of course if you are happy to ...