Search found 3253 matches

by jonescg
Jul 25 2018 7:07am
Forum: Items for Sale - Used
Topic: Samsung SDI cells, 4.2v, 70Ah 70A/210A - EU
Replies: 9
Views: 638

Re: Samsung SDI cells, 4.2v, 70Ah 70A/210A - EU

Interesting cell-top terminal - how do you connect busbars up to them?
by jonescg
Jul 23 2018 9:24pm
Forum: E-Vehicles General Discussion
Topic: EV Myths - add your own!
Replies: 107
Views: 2382

Re: EV Myths - add your own!

So, you are saying, if you buy a new Leaf, or Tesla, you do not have to comply with the manufacturers service schedule to retain full warranty cover ? As far as the ACCC is concerned, the warranty is still valid provided the vehicle has been maintained, so that would include following some kind of ...
by jonescg
Jul 21 2018 8:38am
Forum: Battery Technology
Topic: PCB 18650 connections
Replies: 3
Views: 221

Re: PCB 18650 connections

I think I did see a video of his single cell holders - fine if you never ask more than half an amp from the cells. Flexible printed circuit strips are only good for sensing - milliamps at best. Even thick PCB traces would require lots of copper area to carry more than a few amps without heating up. ...
by jonescg
Jul 20 2018 7:39am
Forum: Battery Technology
Topic: PCB 18650 connections
Replies: 3
Views: 221

Re: PCB 18650 connections

The flexible PCB is definitely only used for the BMS.
The Model 3 battery uses proper busbars with cell terminals wire-bonded to them. The encapsulant ensures uniform temperature and vibration protection.
by jonescg
Jul 18 2018 9:37pm
Forum: Battery Technology
Topic: Bad cell in parallel group - What will happen?
Replies: 6
Views: 316

Re: Bad cell in parallel group - What will happen?

Depends what happens to the cell. An internal short will cause the cell's voltage to drop through self-discharge. Depending on the impedance of the short, the cell's voltage will drop quickly or slowly. In the case of a high impedance short, current will flow from the adjacent cells in parallel into...
by jonescg
Jul 16 2018 1:41am
Forum: E-Vehicles General Discussion
Topic: EV Myths - add your own!
Replies: 107
Views: 2382

Re: EV Myths - add your own!

Hillhater wrote:
Jul 15 2018 11:51pm
Here are a few..
* EVs are economical to own and run
* EVs are cheap to service.
* EVs do not need a transmission.
* EVs will outnumber ICEs within 10 years
Myths or truths? Can't quite tell with you HH ;)
by jonescg
Jul 10 2018 12:58am
Forum: Battery Technology
Topic: Reminder: Don't trust Hobbyking batteries.
Replies: 40
Views: 1420

Re: Reminder: Don't trust Hobbyking batteries.

You guys speak of pouch cells as if expansion is normal - it's not! If a pouch cell is puffing it's because something has gone wrong - either an internal short, physical trauma, over charge or over discharge, or the cells were allowed to get too hot for too long. And yes, any lithium chemistry which...
by jonescg
Jul 07 2018 4:58am
Forum: General Discussion
Topic: Would you be willing to crowdfund ES development?
Replies: 36
Views: 1138

Re: Would you be willing to crowdfund ES development?

An annual payment reminder for $100 would work for me.
by jonescg
Jul 07 2018 4:55am
Forum: Endless-Sphere Wiki
Topic: How many of you really use the wiki?
Replies: 68
Views: 6151

Re: How many of you really use the wiki?

I never use the wiki.

But then again, I also know how to use the search function properly :lol:
by jonescg
Jun 21 2018 11:09pm
Forum: Battery Technology
Topic: mass life cycle testing
Replies: 23
Views: 958

Re: mass life cycle testing

Yes and no. Rated capacity is a useless figure compaired to the actual capacity you can draw from it in the test use case. The first cycle sets the benchmark capacity. I mark the cell as worn when i lost 30% of that initial capacity. Doing a 0.2C discharge test is fun and all but it does not mean a...
by jonescg
Jun 21 2018 3:52am
Forum: Battery Technology
Topic: mass life cycle testing
Replies: 23
Views: 958

Re: mass life cycle testing

In order of most capacity remaining: 4.05>3 at 2A discharge and .7A charge 4.05>3 at 3A discharge and .7A charge 4.1>3 at 2A discharge and .7A charge 4.2>3 at 2A discharge and .7A charge However you need to calculate 'equivalent full cycle life' The number of equivalent full cycles is obtained by di...
by jonescg
Jun 11 2018 9:30pm
Forum: E-Vehicles General Discussion
Topic: Wind and Solar vs Coal, Gasoline, Nuclear
Replies: 2992
Views: 101529

Re: Wind and Solar vs Coal, Gasoline, Nuclear

I'm not so pessimistic about grid scale storage. I doubt that grid scale battery storage will be used in quantities to replicate pumped hydro, but I can see all new RE generators being required to have some amount of battery storage for stability. I think home energy storage is going to take up abou...
by jonescg
Jun 10 2018 8:28am
Forum: E-Vehicles General Discussion
Topic: Wind and Solar vs Coal, Gasoline, Nuclear
Replies: 2992
Views: 101529

Re: Wind and Solar vs Coal, Gasoline, Nuclear

No doubt Hillhater will be along shortly to try and claim it was somehow caused by unreliable wind generators. That's for Hillhater to comment on, but the observation is that while almost 5 GW of coal fired generation went offline, the shortfall was being met by generators elsewhere in the grid - p...
by jonescg
Jun 10 2018 2:16am
Forum: E-Vehicles General Discussion
Topic: Wind and Solar vs Coal, Gasoline, Nuclear
Replies: 2992
Views: 101529

Re: Wind and Solar vs Coal, Gasoline, Nuclear

Interesting to note that four of the five big coal fired power stations in NSW tripped out this weekend. You can see they've been using hydro to fill the gap. NEM1713_10052018.JPG Also it looks like Tassie has got the Basslink interconnector re-established. I think Snowy 2.0 and Tasmania's pumped hy...
by jonescg
Jun 07 2018 8:56pm
Forum: Battery Technology
Topic: Price check on battery packs
Replies: 5
Views: 476

Re: Price check on battery packs

Batteries are actually getting a bit more expensive now. The old supply and demand thing :(
by jonescg
Jun 03 2018 10:51pm
Forum: Electric Aircraft
Topic: Farfles Electric Ultralight.
Replies: 196
Views: 18494

Re: Farfles Electric Ultralight.

Great to see if able to taxi on it's own steam - the e-aero equivalent of spinning the back wheel of a bike :D

How far off a maiden voyage do you think you are?
by jonescg
May 31 2018 7:51am
Forum: Battery Technology
Topic: Wanting to buy a 100 18650 batteries
Replies: 5
Views: 540

Re: Wanting to buy a 100 18650 batteries

I ordered cells from FEP - same place I get the pouches from. They were about AUD$6.30 each landed.
by jonescg
May 24 2018 8:04am
Forum: Battery Technology
Topic: "First Cell Group...?"
Replies: 2
Views: 129

Re: "First Cell Group...?"

If you have a multimeter, set it to test conductivity and check that the pin for B1 is connected to B- (it shouldn't be). That will answer your query.
by jonescg
May 24 2018 3:01am
Forum: Battery Technology
Topic: Voltage versus current pack
Replies: 6
Views: 233

Re: Voltage versus current pack

If your motor and controller is set up to run more efficiently at a higher voltage, then build the 20s pack.
by jonescg
May 24 2018 2:18am
Forum: Battery Technology
Topic: Voltage versus current pack
Replies: 6
Views: 233

Re: Voltage versus current pack

It depends on what your motor/controller combination works best at. If it's got a pole count and turns count such that it spins up to a useful top speed while delivering good torque throughout, then pick the voltage to deliver accordingly. The key benefit to a lower voltage pack is less cells in ser...
by jonescg
May 22 2018 2:12am
Forum: E-Vehicles General Discussion
Topic: Fly-by-wire throttles - two potentiometers?
Replies: 4
Views: 264

Re: Fly-by-wire throttles - two potentiometers?

Thanks Mike, I figured I would only need one of them.

Of all the weird redundancy measures... Surely a couple of 200 ohm resistors on either end of the pot would create a safe buffer and protect against accidental WOT or chopped?
by jonescg
May 22 2018 1:00am
Forum: E-Vehicles General Discussion
Topic: Fly-by-wire throttles - two potentiometers?
Replies: 4
Views: 264

Fly-by-wire throttles - two potentiometers?

Seems as good a place as any to post... I'm looking for an electronic throttle for a car conversion I'm working on. Looks like many late model vehicles (and all electric vehicles :wink: ) use a dual potentiometer system. That is, instead of the usual 3-wire pot (5 V, analog wiper and ground) you see...
by jonescg
May 21 2018 9:24pm
Forum: Battery Technology
Topic: Best battery for my flying bike?
Replies: 9
Views: 396

Re: Best battery for my flying bike?

This crazy contraption: https://www.facebook.com/TodayTonight/videos/1173124852726969/ Only flew because of the massive pile of LiPo I built for it. It was about 6 kWh of 40 C peak cells. The system was powered by six separate motors and controllers, each running on a 100 volt bus. In hindsight high...
by jonescg
May 18 2018 9:58pm
Forum: Large EV General Discussion
Topic: A simple but practical and cheap EV range extender?
Replies: 20
Views: 1364

Re: A simple but practical and cheap EV range extender?

Yeah when you look at the major loads in an EV, they probably stack up like so: Driveline (inverter, motor): 100 kW+ Aircon: ~6 kW Heater: 2-5 kW Pumps_fans: <1 kW Headlights: ~100 W So anything that draws more than 2 kW is best run from the traction pack. At 12 volts, 2 kW is 167 amps - far too muc...
by jonescg
May 18 2018 2:56am
Forum: Battery Technology
Topic: Lithium Batteries Shipping Rules Discussions
Replies: 277
Views: 46520

Re: Lithium Batteries Shipping Rules Discussions

Not sure if this is the best place to put it, but in any case, I recently got a quote to send batteries from Australia to the east coast of the USA. I had an enquiry about a 5 kWh battery build, which I'm happy to do, but shipping it to Baltimore was going to cost AUD$1766. This was for a 1 cubic me...