Search found 672 matches

by kdog
Sep 17 2020 7:37am
Forum: Large EV General Discussion
Topic: Building a pack for Engine Starting
Replies: 6
Views: 246

Re: Building a pack for Engine Starting

4s lifepo4 is good replacement for the LA battery. Has many benefits, but your issue is more the bms side of the project. A quality 500amp+ bms is going to be pricey or difficult to find, you might even need more amps. First thing I'd do is measure your cranking amps with a clamp metre so you know w...
by kdog
Sep 14 2020 10:10am
Forum: Battery Technology
Topic: Stress Testing 3.2V 100AH prismatic cells
Replies: 11
Views: 698

Re: Stress Testing 3.2V 100AH prismatic cells

Nah re read. 3.2v (not exactly high), and dumped in a bucket of water would keep it cool enough to use a lump of wood as a substrate. I'm sure the OP can figure out how to be safe. My ebike battery discharge station is an air cooled coil... hence 'makes a nice bench top heater'. Who said anything ab...
by kdog
Sep 13 2020 11:17pm
Forum: Battery Technology
Topic: Difference in range
Replies: 14
Views: 277

Re: Difference in range

Very true! but all things equal is my presumption, otherwise it's hard to compare anything.
by kdog
Sep 13 2020 10:11pm
Forum: Battery Technology
Topic: Difference in range
Replies: 14
Views: 277

Re: Difference in range

More voltage= more Whrs not more Ah. Probly just a typo... Also, the motor won't 'draw more' just because the battery V is higher. The motor draws the power it needs based on torque and rpm required by you at any particular point. The controller sends the required voltage (always </= to battery V to...
by kdog
Sep 13 2020 9:43pm
Forum: Battery Technology
Topic: Stress Testing 3.2V 100AH prismatic cells
Replies: 11
Views: 698

Re: Stress Testing 3.2V 100AH prismatic cells

If you're just testing one cell at a time, at. 5c that's up to 50amps @3.2v. Most dischargers won't go to 50 amps even if they are 150w I would go and buy a roll of nichrome wire and make your own wire wound resistor. You'll only need a few meters. Wrap it around something heat proof and/or non cond...
by kdog
Sep 13 2020 5:30am
Forum: E-Bike Technical
Topic: Active Equalizer
Replies: 21
Views: 353

Re: Active Equalizer

Is there any reason why you can't use several of these unit together to cover a larger pack. For example 3x4s units for a 12s pack. It seems that you could stick one in middle of a pack without issue as there is no reference to the battery's actual negative.
by kdog
Aug 31 2020 5:43am
Forum: E-Bike Technical
Topic: Battery connections + charging one battery with another
Replies: 4
Views: 170

Re: Battery connections + charging one battery with another

NO! Don't do that. If you plug a charged 36v battery into the charging port of a depleted one (or even with more than about 0.5v diff) you will get massive currents that instantly fry whatever the weakest link is. Hopefully a charging fuse , but most likely your bms as well. If nothing fuses open th...
by kdog
Aug 27 2020 10:44am
Forum: Battery Technology
Topic: How many amps can i put through this nickel
Replies: 3
Views: 149

Re: How many amps can i put through this nickel

Hey lucajo .1mm nickel is quite thin, it will be limited to about 0.5amps per mm of width... so 8mm wide will carry about 4amps. Then you need to find out what your controllers Max output is and provide enough series connections to cover the draw. For example... 40amps peak output of controller = 10...
by kdog
Aug 26 2020 4:10am
Forum: Battery Technology
Topic: New Chinese charger with no ground?
Replies: 16
Views: 276

Re: New Chinese charger with no ground?

2 wire appliances are spored to be double insulated, so normally they have a plastic shell. The smaller fanless plastic chargers don't require a ground bc the outside can't be live. All metal shell appliances should have a ground. I cant think of any metal based appliances in my house (ebike related...
by kdog
Aug 26 2020 12:40am
Forum: E-Scooter and Motorcycle Photos & Videos
Topic: Electric kick bike
Replies: 0
Views: 199

Electric kick bike

Built this out of scrap and spare parts IMG_20200826_32869.jpg Tubing -mates trampoline Rear motor, dead mac repaired built into 20" rim from tipshop (had to buy spokes) Battery:13s 10ah salvaged from a damaged ebike Controller generic 350w NOS from person who never collected. Rest is old mtb stuff ...
by kdog
Aug 24 2020 12:31am
Forum: E-Bike Non-hub Motor Drives
Topic: Shimano Steps
Replies: 1
Views: 141

Re: Shimano Steps

Welcome to the world of proprietary integrated systems with little user friendly attributes. Unfortunately for you (bc it's what you don't want to do) I would suggest taking it to a bike shop with shimano steps diagnostic capability. They can review the error codes and see what the issue is. I can i...
by kdog
Aug 22 2020 9:12am
Forum: Battery Technology
Topic: Help! Electric motion battery tripping.
Replies: 2
Views: 103

Re: Help! Electric motion battery tripping.

Calm down Bob, no need for all that aggression. j2000 has just found this forum and gets you... What a lousy intro..., its sposed to be a helpful place , not somewhere you get abused on your ?first post. j2000 ignore Bob. After a fall or impact when things go awry, I would start looking for a broken...
by kdog
Aug 19 2020 7:33am
Forum: E-Bike Technical
Topic: Ebike battery question
Replies: 27
Views: 373

Re: Can anyone please tell me the exact configuration of this battery pack - (See photos)

Yep, it's 13s....even says so on the label :lol: don't really need pics of the other side. Bms wires also confirm it.
by kdog
Aug 19 2020 6:37am
Forum: Battery Technology
Topic: Slight gap in contact, is it safe?
Replies: 4
Views: 201

Re: Slight gap in contact, is it safe?

Potentially solder the bolted ends as well if you can't get good contact.
by kdog
Aug 19 2020 6:35am
Forum: Battery Technology
Topic: Slight gap in contact, is it safe?
Replies: 4
Views: 201

Re: Slight gap in contact, is it safe?

If each of the copper bus's are bolted together at each end, and the nickel is spot welded to the cell then I can't see any issue. The current flow will be from one bus to the other mainly via the bolted ends. Thus the potential difference across those to pieces of copper will be negligible so there...
by kdog
Aug 18 2020 5:55pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: advanced battery meter for 10s batteries
Replies: 11
Views: 310

Re: advanced battery meter for 10s batteries

When I build a battery I either leave the bms accessible or even better, have a parallel 2nd set of sensor leads easily available for checking cell V.
by kdog
Aug 18 2020 9:25am
Forum: E-Scooter and Motorcycle General Discussion
Topic: advanced battery meter for 10s batteries
Replies: 11
Views: 310

Re: advanced battery meter for 10s batteries

I built a 4 way parallel sensor lead harness that goes between the bms and cells with the 3rd group going to the reaktor. That way if I want, I can discharge through the bms and monitor cell voltages and lvc to make sure the bms is functioning properly.
by kdog
Aug 18 2020 9:19am
Forum: E-Scooter and Motorcycle General Discussion
Topic: advanced battery meter for 10s batteries
Replies: 11
Views: 310

Re: advanced battery meter for 10s batteries

I've been using a turnigy reaktor for several years now. It's a great machine. Does 10s li-ion. All the usual stuff that an rc charger/discharger does including IR. High powered too.
by kdog
Aug 15 2020 5:22am
Forum: E-Vehicles General Discussion
Topic: Hub Motor Vibrating when loaded! (even if not connected to ESC)
Replies: 3
Views: 193

Re: Hub Motor Vibrating when loaded! (even if not connected to ESC)

Do they have any free play? Maybe the rotor and stator are rubbing against each other with your weight on them. Are there any marks anywhere? Some bearing issues require weighted rotation to replicate. Is it a fine high frequency vibration or more a growling low frequency one? Other issues could be ...
by kdog
Aug 14 2020 5:57pm
Forum: E-Vehicles General Discussion
Topic: Hub Motor Vibrating when loaded! (even if not connected to ESC)
Replies: 3
Views: 193

Re: Hub Motor Vibrating when loaded! (even if not connected to ESC)

Sounds like a ball bearing is shot. Did you check them?
by kdog
Aug 12 2020 9:19am
Forum: Motor Technology
Topic: Replacement motor controller help
Replies: 2
Views: 139

Re: Replacement motor controller help

Cyclone Taiwan should have everything you need.
http://www.cyclone-tw.com
by kdog
Aug 09 2020 2:13am
Forum: Battery Technology
Topic: Drawing slightly over rated e bike battery amps
Replies: 6
Views: 174

Re: Drawing slightly over rated e bike battery amps

Lots have an 'overcurrent' shut down in the case of a short but it's usually 2-3times rated current. And as john61 said they sometimes just burn... Which shuts them off ha!
If your battery is rated to 50 amps, I wouldn't worry about 55, 10%extra isnt worth worrying about.
by kdog
Aug 09 2020 2:00am
Forum: Battery Technology
Topic: Spot Welding Copper Strips to 18650 Battery Cells
Replies: 354
Views: 62088

Re: Spot Welding Copper Strips to 18650 Battery Cells

Hey garolittle
Whats the conductivity? IACS?
Cost? And where did you get it.
Cheers for info.
by kdog
Aug 08 2020 11:29pm
Forum: Battery Technology
Topic: Australian RCM certified 58.8V 10A charger sources?
Replies: 2
Views: 96

Re: Australian RCM certified 58.8V 10A charger sources?

Why does it have to be specifically aus rcm certified? Or can some other standard be acceptable. Don't know if this is an answer to your question but would a quality charger such as the satiator suit your needs? Highly programmable, does up to 63v @8amps. Worldwide certification etc. Find it at Ebik...