Search found 73 matches
- Feb 25 2021 8:16am
- Forum: Battery Technology
- Topic: 10S4P with Samsung 29E vs 10S5P with Samsung 26H
- Replies: 8
- Views: 236
Re: 10S4P with Samsung 29E vs 10S5P with Samsung 26H
Who is the vendor of the unoriginal pack? I am really surprised that someone wants to sell such crappy sells at bosch prices. See here: https://www.e-bike-vision.de/product/powerpack-for-bosch-classic/en In fact the 468Wh pack has Samsung 26J cells (not 26H) but AFAIK the characteristics are the sa...
- Feb 25 2021 4:14am
- Forum: Battery Technology
- Topic: 10S4P with Samsung 29E vs 10S5P with Samsung 26H
- Replies: 8
- Views: 236
Re: 10S4P with Samsung 29E vs 10S5P with Samsung 26H
Thanks! Then I think I'll stick with the original Bosch 400Wh since I've been extremely happy with the cycle life of my pack (8 years and about 30'000km). Another advantage is that being a 4P, it is slighlty lighter than a 5P. Having more range would be great but I doubt that going from 400 to 468Wh...
- Feb 23 2021 7:46am
- Forum: Battery Technology
- Topic: 10S4P with Samsung 29E vs 10S5P with Samsung 26H
- Replies: 8
- Views: 236
10S4P with Samsung 29E vs 10S5P with Samsung 26H
Hi, I'm about to buy a new battery pack for my Bosch ebike. My ebike is 36V with a 350W nominal motor. However afaik the motor can draw up to 540W peak. Not sure whether this is exact but I guess that max amperage should always be <18A anyway. I'm considering two different packs: - 10S 4P made with ...
- Dec 24 2020 1:24pm
- Forum: EBike Non-hub Motor Drives
- Topic: Bosch mid drive with vesc controller
- Replies: 41
- Views: 10339
Re: Bosch mid drive with vesc controller
@mechhead If I understand it correctly, you use a VESC 4.12 in sensorless mode with the Bosch motor. I would be interested to know if you use sensorless BLDC mode or sensorless FOC mode and whether you experience cogging when the motor starts to assist at low RPM? I'd be interested to do the same i....
- Aug 15 2020 10:50am
- Forum: Battery Technology
- Topic: BMS or Hobby Charger
- Replies: 7
- Views: 1236
Re: BMS or Hobby Charger
Using that BMS with the charger is safer and simpler I'd say, since you don't need to mess around with the Balance plug everytime you want to charge your scooter up. Which for me can be daily. I'm also considering using a hobby charger (iCharger 3010B) instead of a BMS for a Li-ion (10S6P samsung 2...
- Jun 14 2020 8:29pm
- Forum: Battery Technology
- Topic: 18650 spot welding -how to- ULTIMATE REPOSITORY
- Replies: 790
- Views: 195983
Re: 18650 spot welding -how to- ULTIMATE REPOSITORY
OK guys so i've just built a B52 Bomber battery 22S10P using LG MJ1 3500 mAh cells i've used 5mm wide 0.2mm thick solar panel bus tape - its tinned copper. scotchbrite the tops/bottoms of the cells and tinn them with solder and 80W iron, takes less than a second using fairly heavy gauge solder. Int...
- Jun 13 2020 4:33pm
- Forum: Battery Technology
- Topic: 18650pack cell protection idea. PTC + fuse & diode).
- Replies: 25
- Views: 1682
Re: 18650pack cell protection idea. PTC + fuse & diode).
In my case, the battery would be used without BMS and would be charged with a balance RC charger. Since the balance wires must be connected/disconnected on every charge, withthe balance plug sitting outside the pack, I'd have seen some potential benefits if fuses placed on the balance leads (the fus...
- Jun 12 2020 11:50pm
- Forum: Battery Technology
- Topic: 18650pack cell protection idea. PTC + fuse & diode).
- Replies: 25
- Views: 1682
Re: 18650pack cell protection idea. PTC + fuse & diode).
If you want to go that route then you need a regular fuse, never ever put passive or active parts between the bms and the cells. Sorry I don't get it. A regular fuse (i.e. non PTC) is a passive element so he cannot go that route either then. Do you mean he should only use a regular fuse after the B...
- Jun 10 2020 8:53am
- Forum: Battery Technology
- Topic: BOSS LEVEL CUSTOM SPOT WELDER
- Replies: 471
- Views: 63105
Re: BOSS LEVEL CUSTOM SPOT WELDER
Really sorry to read that, Rojitor. Take care!
- Jun 08 2020 3:48am
- Forum: Battery Technology
- Topic: BOSS LEVEL CUSTOM SPOT WELDER
- Replies: 471
- Views: 63105
Re: BOSS LEVEL CUSTOM SPOT WELDER
I did this weekend a shockproof pack for a Trampa mountainboard. My customer is more of an animal than a human so it really needs to be rock solid to last in his hands. I used both welding and the neodinium magnets technique. The welds are really really unlikely to fail due to vibrations and contin...
- Jun 03 2020 9:07am
- Forum: Battery Technology
- Topic: DIY Li-ion battery: first connect cells in series, then in parallel
- Replies: 22
- Views: 886
Re: DIY Li-ion battery: first connect cells in series, then in parallel
If your pack will end up all pretty much permanently spotwelded together, there really is not much difference, S&P connections can also happen at the same time with a laser-cut plate rather than using strips. That's what I wanted to read :) Indeed the pack will always remain in the 10S6P format...
- Jun 03 2020 9:05am
- Forum: Battery Technology
- Topic: DIY Li-ion battery: first connect cells in series, then in parallel
- Replies: 22
- Views: 886
Re: DIY Li-ion battery: first connect cells in series, then in parallel
If after riding the balance is off, takes more than 5min to correct, either get a new checker (they're cheap) or get a faster balancer. Good point! I think that's what I'll do. Anyway the balancing power is probably not going to be an issue (my RC charger can do up to 500mA to balance cells). That'...
- Jun 03 2020 7:56am
- Forum: Battery Technology
- Topic: DIY Li-ion battery: first connect cells in series, then in parallel
- Replies: 22
- Views: 886
Re: DIY Li-ion battery: first connect cells in series, then in parallel
.. unless of course you plan to “go commando” with no BMS ? :o In fact this is what I plan to do: no BMS but charging using a hobby balance charger (incl. temperature sensor) + use 2 lipo checkers as low voltage alarms, as suggested by Shawn McCarty in this video. https://www.youtube.com/watch?v=pl...
- Jun 03 2020 6:50am
- Forum: Battery Technology
- Topic: DIY Li-ion battery: first connect cells in series, then in parallel
- Replies: 22
- Views: 886
Re: DIY Li-ion battery: first connect cells in series, then in parallel
Thanks for your reply dogman dan. I think there may be some misunderstanding about what I intend to do. I understand that building series first effectively means building 6 10S1P batteries. But if all the individual cells (from all these 6 batteries) have exactly the same voltage, I don't get why it...
- Jun 02 2020 12:21pm
- Forum: Battery Technology
- Topic: DIY Li-ion battery: first connect cells in series, then in parallel
- Replies: 22
- Views: 886
Re: DIY Li-ion battery: first connect cells in series, then in parallel
I think I'll end up using M2 bolts and nylok nut instead of solder to secure the tabs between cells. The connections would look like this (I may still add a washer below the nylok nut): https://i.imgur.com/DhFBqbm.png Keeping everything Nickel plated should avoid any corrosion issue. The series conn...
- May 28 2020 1:23am
- Forum: Battery Technology
- Topic: DIY Li-ion battery: first connect cells in series, then in parallel
- Replies: 22
- Views: 886
Re: DIY Li-ion battery: first connect cells in series, then in parallel
:shock: What you have shown is impossible to assemble with any voltage in the cells, and would burst into flames if you tried to charge it ! If you Do not understand the problem here, ..or the point about the BMS requirements, then i urge you not to attempt to assemble a battery until you have rese...
- May 28 2020 1:21am
- Forum: Battery Technology
- Topic: DIY Li-ion battery: first connect cells in series, then in parallel
- Replies: 22
- Views: 886
Re: DIY Li-ion battery: first connect cells in series, then in parallel
A common pack build might use a style of nickel bus that is shaped like a ladder, and it accomplishes the series and parallel connections at the same time with a single layer of nickel sheet. I'm thinking about building a DIY 10S6P battery pack using new Samsung 29E cells bought with Z-solder tabs ...
- May 28 2020 12:59am
- Forum: Battery Technology
- Topic: DIY Li-ion battery: first connect cells in series, then in parallel
- Replies: 22
- Views: 886
Re: DIY Li-ion battery: first connect cells in series, then in parallel
I was thinking about a situation like this, considering for example a 10S3P battery. https://i.imgur.com/7CuwxDQ.png Suppose that I have 30 cells each with a capacity of 1C and I start by making the 3 series strings (grey connections) and then start with the first parallel connection (blue). At this...
- May 27 2020 2:59pm
- Forum: Battery Technology
- Topic: Any lipo checker that is not powered only from first cell?
- Replies: 17
- Views: 523
Re: Any lipo checker that is not powered only from first cell?
For one hour, it would only draw 50MaHr of pack capacity. For a 10AH pack, it would take 200 hours to deplete pack (10,000Mahr/50MaHr = 200). For a one hour ride, you would use about 1/2 percent of pack. Is it possible to calculate the voltage difference that would result between the first cell (po...
- May 27 2020 2:18pm
- Forum: Battery Technology
- Topic: DIY Li-ion battery: first connect cells in series, then in parallel
- Replies: 22
- Views: 886
Re: DIY Li-ion battery: first connect cells in series, then in parallel
I do not grok at all what you are saying about different capacities while building - I think you are imagining something there that is not the case. All cells should be at exactly the same SoC/voltage, capacity/SoH etc before you start. IMO do not bother with scrap cells. My wording was probably in...
- May 27 2020 11:19am
- Forum: Battery Technology
- Topic: DIY Li-ion battery: first connect cells in series, then in parallel
- Replies: 22
- Views: 886
DIY Li-ion battery: first connect cells in series, then in parallel
Hi, when building a Li-ion battery, it seems usual to first build groups of parallel cells and then connect these in series. Is it actually safe to do it conversely: first build groups of cells in series and then connect these groups in parallel? I understand that groups of cells connected in series...
- May 25 2020 3:17am
- Forum: Battery Technology
- Topic: Any lipo checker that is not powered only from first cell?
- Replies: 17
- Views: 523
Re: Any lipo checker that is not powered only from first cell?
Put a switch on first input wire to lipo checker.....just turn it off when not in use and it does not draw current. A switch wouldn't really help in my application because I'd like to use it while riding so that it monitors the voltage continuously and beeps if one cell gets too low, in replacement...
- May 25 2020 3:06am
- Forum: Battery Technology
- Topic: (semi)-solderless design: Attaching cells with solder tags using brass bolts
- Replies: 16
- Views: 579
Re: (semi)-solderless design: Attaching cells with solder tags using brass bolts
After reconsidering @Hillhater suggestions, I may also consider soldering the U tabs on the copper bus bars instead of using brass bolts but this is still to be decided. Anyway, here are a few picture of the layout for a 10S6P battery: top view: https://i.imgur.com/r40b5UB.png bottom view: https://i...
- May 22 2020 11:29am
- Forum: Battery Technology
- Topic: (semi)-solderless design: Attaching cells with solder tags using brass bolts
- Replies: 16
- Views: 579
Re: (semi)-solderless design: Attaching cells with solder tags using brass bolts
...50-100+ Multiples of unproven small bolted connections, lies in the increased probability of a bad contact, loose nut, corrosion, etc. Reliability is improved by keeping things simple with temporary connections and part count at a minimum A spot-welded or soldered connection can also fail, espec...
- May 22 2020 11:15am
- Forum: Battery Technology
- Topic: Any lipo checker that is not powered only from first cell?
- Replies: 17
- Views: 523