Search found 58 matches

by BotoXbz
Mar 15 2019 4:55pm
Forum: Motor Technology
Topic: Serious FOCer (84V VESC 6 based controller)
Replies: 13
Views: 370

Re: Serious FOCer (84V VESC 6 based controller)

subscribed. Do you have an approximate BOM cost yet? Was actually waiting for someone to do the hard work on a cheap and higher voltage VESC6 design :D Once you make this open source (and I have some spare time) I'll probably look into redoing the layout so it fits in the BBSHD like the original con...
by BotoXbz
Mar 14 2019 3:09am
Forum: E-Bike Technical
Topic: Help/Volunteer needed with Bafang Battery / BMS
Replies: 0
Views: 44

Help/Volunteer needed with Bafang Battery / BMS

Hi, I wrote my own open source BMS firmware for the Chinese smart BMS to use it with my Xiaomi M365 electric scooter. Details here: https://github.com/BotoX/xiaomi-m365-compatible-bms Now I want to make it work with Bafang systems just like the original Battery/BMS from Bafang does. In order to impl...
by BotoXbz
Mar 09 2019 6:15am
Forum: Battery Technology
Topic: What battery to choose after your last one burned your house.
Replies: 39
Views: 1202

Re: What battery to choose after your last one burned your house.

18650 is the only way. the reason why a single cell pouch fail is so destructive is because of the amount of energy stored and the bag itself provides zero protection. a single 18650 hold roughly 10~12Wh, cannot puff up and at worst so some venting at the top. oh, and you need a hammer and chisel t...
by BotoXbz
Mar 03 2019 6:56pm
Forum: Battery Technology
Topic: AliExpress battery pack unboxing
Replies: 71
Views: 2546

Re: 79.8V before refactoring, 82.4 after?

Ok this is new to me. A few weeks ago I started to disassemble the AliExpress battery pack with the goal of "bringing it up to spec". At that time it read 79.8V as measured off of the 120A dumb BMS supplied. This past weekend I finally got it (mostly) back together (minus the BMS) and for kicks I m...
by BotoXbz
Mar 03 2019 7:16am
Forum: Battery Technology
Topic: DIY 14S10P lasercut full wooden enclosure/cell holder
Replies: 20
Views: 797

Re: DIY 14S10P lasercut full wooden enclosure/cell holder

Finally got around to spotweld this beast: https://cloud.botox.bz/s/9PK4P8wszj3r487/preview https://cloud.botox.bz/s/D7n8xQDYpEWxjeF/preview Waiting for some Turnigy 12AWG silicone wire from hobbyking to finish it. For the negative discharge wire I'll cut 10 short nickel pieces which will go towards...
by BotoXbz
Feb 25 2019 5:03am
Forum: Battery Technology
Topic: PURE Nickel strip
Replies: 14
Views: 438

Re: PURE Nickel strip

I bought this one twice, it's legit: https://www.aliexpress.com/item/Pure-Nickel-Strip-for-Scientific-research-18650-battery-welding-Size-0-2-8mm/32739610924.html Scratched and left it in saltwater over night, no rust. Also soft and doesn't break after bending it often. The seller also has other si...
by BotoXbz
Feb 23 2019 9:00pm
Forum: Vendor Relations Corner
Topic: Sunkko 737G and buying at Banggood.com
Replies: 2
Views: 227

Re: Sunkko 737G and buying at Banggood.com

I always pay with PayPal at Chinese places (except for AliExpress, they don't offer it but their support is quite good) which didn't let me down so far and also has a program where they'll pay for your shipping costs if you want to return an item. But obviously the Battery + FET bank welders are muu...
by BotoXbz
Feb 22 2019 8:52pm
Forum: Battery Technology
Topic: Confirmation: 20s BMS --> 2x 10S packs
Replies: 3
Views: 171

Re: Confirmation: 20s BMS --> 2x 10S packs

Sure this will work fine, there is no real difference here between this and a "normal" 20S battery. But it sounds like you are confusing what a BMS does. A BMS can only cut off the battery (like a switch) or slowly discharge some cells to balance the pack. Your charger will need to have a high enoug...
by BotoXbz
Feb 20 2019 3:06pm
Forum: E-Bike Non-hub Motor Drives
Topic: Bafang M400 G330.250 Configuration
Replies: 4
Views: 266

Re: Bafang M400 G330.250 Configuration

Also unrelated to your question but of interest to me: Does your display show the remaining capacity and maybe even single cell voltages of the battery? Is your battery connected to the motor only with two wires or are there additional wires? Battery info is available: b01 = temperature b04 = 45967...
by BotoXbz
Feb 20 2019 10:56am
Forum: E-Bike Non-hub Motor Drives
Topic: Bafang M400 G330.250 Configuration
Replies: 4
Views: 266

Re: Bafang M400 G330.250 Configuration

The cable that goes from the display to the motor, that's the UART cable. Check if it has a HIGO connector that you can unplug, the programming cable attaches to the motor through that. Also unrelated to your question but of interest to me: Does your display show the remaining capacity and maybe eve...
by BotoXbz
Feb 20 2019 6:01am
Forum: E-Bike General Discussion
Topic: Help: 72v 20s7p battery design and/or configuration
Replies: 5
Views: 151

Re: Help: 72v 20s7p battery design and/or configuration

What kind of current is this pack made for?
You have some series connections where only one cell has the series connection to the next group.
If your pack was welded with normal nickel strip that'd limit your current to 6-7A or heat up and kill those cells.
by BotoXbz
Feb 19 2019 12:56pm
Forum: Battery Technology
Topic: PURE Nickel strip
Replies: 14
Views: 438

Re: PURE Nickel strip

I bought this one twice, it's legit: https://www.aliexpress.com/item/Pure-Nickel-Strip-for-Scientific-research-18650-battery-welding-Size-0-2-8mm/32739610924.html Scratched and left it in saltwater over night, no rust. Also soft and doesn't break after bending it often. The seller also has other siz...
by BotoXbz
Feb 14 2019 5:08pm
Forum: Battery Technology
Topic: DIY 14S10P lasercut full wooden enclosure/cell holder
Replies: 20
Views: 797

Re: DIY 14S10P lasercut full wooden enclosure/cell holder

As far as I know 18650s don't "swell" since they're in a thick steel can. The metal expands a bit when it gets warm but I hope that won't be an issue. What I didn't quiet realize is how heavy 7kg actually are, this thing is MASSIVE. Pictures: https://cloud.botox.bz/s/X2i2rczA4Sbs2A9 & https://cloud....
by BotoXbz
Feb 14 2019 5:35am
Forum: Battery Technology
Topic: DIY 14S10P lasercut full wooden enclosure/cell holder
Replies: 20
Views: 797

Re: DIY 14S10P lasercut full wooden enclosure/cell holder

Seemed to me like a stupid idea but turns out that it might be a good one. Kudos on the cuts, they look very clean, nice work so far! You could even create some channels in the last layers of each sides of the plywood so that the strips are encased and protected, this way they wouldn't protrude out...
by BotoXbz
Feb 13 2019 10:20pm
Forum: Battery Technology
Topic: DIY 14S10P lasercut full wooden enclosure/cell holder
Replies: 20
Views: 797

Re: DIY 14S10P lasercut full wooden enclosure/cell holder

Final battery layout: https://cloud.botox.bz/s/6SkajnrkYCQcT6r/preview (didn't draw all the series connection because lazy) Gonna lasercut the last parts tomorrow. The layout matters for laser cutting as 50% of the holes for the outermost two plates will be of smaller diameter for the positive side....
by BotoXbz
Feb 12 2019 5:00am
Forum: Battery Technology
Topic: bluetooth BMS?
Replies: 949
Views: 60471

Re: bluetooth BMS?

For a more accurate current reading you can also remove these two small resistors: https://cloud.botox.bz/s/2ipzTsJNWQ222TH (disregard the big one) They divide the shunt voltage in half, the shunt resistor value is already way too small if one reads the datasheet recommendation for the TI ADC. And t...
by BotoXbz
Feb 10 2019 6:25am
Forum: E-Bike Non-hub Motor Drives
Topic: Bafang BBSHD Error 30
Replies: 4
Views: 175

Re: Bafang BBSHD Error 30

Error 30 is a generic communication error. So basically your display is not getting a response from your motor, are you sure it is even working at all? Your programming cable is trying to send something but doesn't seem to get an answer either. So either something is wrong with your wiring or your c...
by BotoXbz
Feb 07 2019 1:57pm
Forum: Battery Technology
Topic: DIY 14S10P lasercut full wooden enclosure/cell holder
Replies: 20
Views: 797

Re: DIY 14S10P lasercut full wooden enclosure/cell holder

Status update:
Image

Sadly ran out of time, can cut the remaining 4 pieces (2 plates x 15min) next Thursday.
The cells hold super well, they need like 5-10kg of pressure to get in.
So I'm not even gonna glue the wooden sheets together, no need.
by BotoXbz
Feb 04 2019 8:26am
Forum: E-Bike Technical
Topic: mislabeled BMS ! what to do?
Replies: 8
Views: 189

Re: mislabeled BMS ! what to do?

In the first picture I can see B- on the bottom left, P- in the middle and P- on the right lol.
Second picture B- matches, P- matches and the second P- is C- there.
Could you take the cover off and make another picture?
The current shunt resistors should be at B-.
by BotoXbz
Feb 04 2019 7:49am
Forum: E-Bike Technical
Topic: mislabeled BMS ! what to do?
Replies: 8
Views: 189

Re: mislabeled BMS ! what to do?

Could you post an image of the PCB?
by BotoXbz
Feb 03 2019 11:00am
Forum: Battery Technology
Topic: DIY 14S10P lasercut full wooden enclosure/cell holder
Replies: 20
Views: 797

Re: DIY 14S10P lasercut full wooden enclosure/cell holder

I am unable to view the picture of the plywood section, but I think I have the idea from your description. Rather than ending up with a solid block, consider the option of using perhaps four of the 4mm sheets to allow for air circulation and to save some weight. It's an interactive 3D viewer from a...
by BotoXbz
Feb 03 2019 9:56am
Forum: Battery Technology
Topic: DIY 14S10P lasercut full wooden enclosure/cell holder
Replies: 20
Views: 797

Re: DIY 14S10P lasercut full wooden enclosure/cell holder

john61ct wrote:
Feb 03 2019 8:55am
G10 FR4 laminate board
It's a 60W CO2 laser so I'd only be able to cut very thin sheets of this material at slow speeds from the info I found on the net.
Might make sense to use this as the first and last sheet if I can source it easily.
by BotoXbz
Feb 03 2019 7:28am
Forum: Battery Technology
Topic: DIY 14S10P lasercut full wooden enclosure/cell holder
Replies: 20
Views: 797

DIY 14S10P lasercut full wooden enclosure/cell holder

After thinking about different ways to build my 14S10P triangle battery for my BBSHD hardtail I arrived at the following design: https://a360.co/2Utuo6G I have access to a lasercutter at uni and am planning to cut the shape from 4-8mm poplar plywood sheets and glue them together to form one big soli...