Search found 886 matches

by eMark
Sep 24 2022 3:11pm
Forum: Battery Technology
Topic: one cell group wont fully charge
Replies: 78
Views: 1070

Re: one cell group wont fully charge

Iteresting when comparing these two: https://cellsaviors.com/pack-builder ... and ... https://www.repackr.com/ using same identical 41 mAh capacities for that 13s3p (what-if) salvaged 18650 DIY build. Using the SAME CELL CAPACITY DATA from my previous post (https://endless-sphere.com/forums/viewtopi...
by eMark
Sep 23 2022 2:19pm
Forum: Battery Technology
Topic: one cell group wont fully charge
Replies: 78
Views: 1070

Re: one cell group wont fully charge

As a teaser, Repackr's individual group capacities were closer to the average capacity of the entire pack. That's the goal, right??? Right; especially with an ebike performance pack versus a powerbank with lower amp drain. The more p-groups the better (at least 5p). Personally i wouldn't use 7 thos...
by eMark
Sep 22 2022 3:54pm
Forum: Battery Technology
Topic: one cell group wont fully charge
Replies: 78
Views: 1070

Re: one cell group wont fully charge

That link ... https://www.repackr.com/ ... only lists several replies from 2020. There is no further link to open up the actual builder for entering cell capacities and pack size(s). Found this link ... https://cellsaviors.com/pack-builder ... that basically does same. It would be interesting if abl...
by eMark
Sep 22 2022 8:57am
Forum: Battery Technology
Topic: one cell group wont fully charge
Replies: 78
Views: 1070

Re: one cell group wont fully charge

If anyone wants to try out that 'rePackr' website https://www.repackr.com/ that m3vuv mentioned, you can use the string of data below. The site is used to determine the optimal arrangement of measured cell mAH capacities to put into each parallel group so that they are close to each other. Use this...
by eMark
Sep 20 2022 12:15pm
Forum: Battery Technology
Topic: Buying a new battery: your advice sought
Replies: 75
Views: 1471

Re: Buying a new battery: your advice sought

After 7 years, age 64-71 I retired from kit sales and support. My second retirement. My first at 57 to relax in Minnesota. Winona is God's beautiful country nestled between Mississippi R(fishing) and Limestone Bluffs. As good a place as any to retire https://encrypted-tbn0.gstatic.com/images?q=tbn:...
by eMark
Sep 20 2022 11:47am
Forum: Battery Technology
Topic: Buying a new battery: your advice sought
Replies: 75
Views: 1471

Re: Buying a new battery: your advice sought

I think you spent too much time chumming with Curtis. Don't have a clue who you're referencing. Who is Curtis or is this your sense of wry humor? Honestly i'd never buy a EM3ev ... the reason being that your EM3e v posts are of no real substance. Just the same ol' same ol'. If your avatar was more ...
by eMark
Sep 20 2022 11:02am
Forum: Battery Technology
Topic: Buying a new battery: your advice sought
Replies: 75
Views: 1471

Re: Buying a new battery: your advice sought

Apparently you hadn't read my previous post 1 minute before your lengthy post. How many other ES members have praised EM3ev batteries? To my knowledge not many other than 2or 3. Your comparison of EM3ev batteries to Bafang Ultra Max or BBS02 doesn't ring true. For you to give the impression that Ama...
by eMark
Sep 20 2022 10:38am
Forum: Battery Technology
Topic: Buying a new battery: your advice sought
Replies: 75
Views: 1471

Re: Buying a new battery: your advice sought

To be unfront honest no more impressed by your on-going pro EM3ev posts than i am with your sporty avatar. Actually your pro EM3ev posts are getting to be the same ol' same ol' ... https://endless-sphere.com/forums/download/file.php?avatar=37287_1544738461.jpg Others too may be wondering why you see...
by eMark
Sep 20 2022 9:59am
Forum: Battery Technology
Topic: Buying a new battery: your advice sought
Replies: 75
Views: 1471

Re: Buying a new battery: your advice sought

But EM3ev is a superior builder. I did a custom UPP when EM3ev was backlogged and slow as heck. Would have never heard about EM3ev Chinese batteries if not for your posts and distain for UPP Chinese batteries. Amazon lists a ton of UPP batteries as well as other Chinese brands: YOSE, ANKLOUS, QZF a...
by eMark
Sep 18 2022 3:56pm
Forum: Battery Technology
Topic: Buying a new battery: your advice sought
Replies: 75
Views: 1471

Re: Buying a new battery: your advice sought

Those prices are outrageous. But with inflation and demand, that appears to be where the market is at I guess. I paid almost exactly $5/cell (liionwholesale) for the gray-label P42As last year after shipping. Even today, I personally wouldn't pay more than $5/cell. Batteries were suppose to get che...
by eMark
Sep 18 2022 9:43am
Forum: Battery Technology
Topic: Buying a new battery: your advice sought
Replies: 75
Views: 1471

Re: Buying a new battery: your advice sought

Even more interesting is the new Molicel P45B cells. if I was looking to build a pack in the near future that'd probably be my choice (although I'd probably wait to see how Pajda's cycle tests compare first if I wasn't in a rush. https://www.molicel.com/inr21700-p45b/ ... more than a few DIY enthus...
by eMark
Sep 17 2022 5:46pm
Forum: Battery Technology
Topic: Problem with battery 72v 20ah
Replies: 9
Views: 342

Re: Problem with battery 72v 20ah

That usually indicates the BMS has detected a cell problem outside it's normal limitations, and has shut off the charge port to prevent cell damage that could lead to a fire. A well-designed BMS will do this, and will lock out charging (unless reset) so the battery won't catch fire from a damaged c...
by eMark
Sep 16 2022 3:37pm
Forum: Battery Technology
Topic: Buying a new battery: your advice sought
Replies: 75
Views: 1471

Re: Buying a new battery: your advice sought

Likely most have never heard of Molicel. next, they're overpriced for the eBike market from the pricing I find. See this ES thread posted in April of 2022 for price comparisons ... https://endless-sphere.com/forums/viewtopic.php?t=115915 Molicel P42A 21700 4200mAh 45A favored for both performance a...
by eMark
Sep 15 2022 3:51pm
Forum: Battery Technology
Topic: one cell group wont fully charge
Replies: 78
Views: 1070

Re: one cell group wont fully charge

i was just going to test the cells in the lower groups.may go for a 2 or 3 mile ride and look at the ballace then. Apparently the best (least variance) you can achieve with your 'smart' BMS has already been achieved after 35 hours. Seven of the p-groups were balance charged to 4.165V, three balance...
by eMark
Sep 15 2022 10:41am
Forum: Battery Technology
Topic: Buying a new battery: your advice sought
Replies: 75
Views: 1471

Re: Buying a new battery: your advice sought

Doug at California eBike sold UPP batteries and we saw an unacceptably high failure rate. Warranty coverage was abysmal. The shop took a beating honoring the warranty. When a UPP battery caused a garage fire UPP was untouchable and shop insurance paid the $50,000 claim. My EM3ev packs have outlived...
by eMark
Sep 15 2022 8:46am
Forum: Battery Technology
Topic: one cell group wont fully charge
Replies: 78
Views: 1070

Re: one cell group wont fully charge

Hi all,i have a homebrew 13s 10p pack with a chineese smart bms over bt,i notice cell groupe 9 never charges more than 4.108v any ideas why this is? all other groups of cells seem fine,cheers. In the first photo 11th10p is 1mV lower than 9th10p (groupe 9). One reason for 9th10p & 11th10p having...
by eMark
Sep 14 2022 6:55pm
Forum: Battery Technology
Topic: one cell group wont fully charge
Replies: 78
Views: 1070

Re: one cell group wont fully charge

this is the state of it at the moment,been on charge about 35hrs now. https://endless-sphere.com/forums/download/file.php?id=323413 So, the green charge light was on for over 30 hrs (35)? The purpose being that the BMS would slowly (ever so slowly) balance the parallel groups via discharge balancin...
by eMark
Sep 14 2022 5:23pm
Forum: EBike Technical
Topic: Tire mount directly to Direct Drive motor
Replies: 6
Views: 149

Re: Tire mount directly to Direct Drive motor

Maybe this will help you guys find a suitable solid tire solution ... https://ae01.alicdn.com/kf/H79fb2fbfb3034b4ab51b9690404056d2j.jpg The inside dimensions of your DDR-40 motor rim are: 222mm (8.74") by 46.5mm (1.83") https://www.aliexpress.com/item/2251832693010988.html?gatewayAdapt=4it...
by eMark
Sep 14 2022 1:55pm
Forum: Battery Technology
Topic: one cell group wont fully charge
Replies: 78
Views: 1070

Re: one cell group wont fully charge

That's a p-group variance of ONLY 0.035V (35mV). That's about the best you could expect to get from any BMS after 35 hrs considering the unknown condition of your 130 cells. If it were me (while waiting for your litokalla lii500) i'd go for a ride discharging your 13s10p build to around 44V to 45V. ...
by eMark
Sep 14 2022 10:34am
Forum: Battery Technology
Topic: one cell group wont fully charge
Replies: 78
Views: 1070

Re: one cell group wont fully charge

there are 9x 15q of 1.5ah cells and one samsung 2.5ah cell per groupe,cant remember the part number tho,the pack only charges to 53.4v max for some reason. That's sufficient reason to manually Top (discharge) Balance the thirteen 10p groups (via discharge as suggested) before again bulk charging to...
by eMark
Sep 13 2022 4:26pm
Forum: Battery Technology
Topic: one cell group wont fully charge
Replies: 78
Views: 1070

Re: one cell group wont fully charge

If I wanted to follow similar suit and build a 14S 5P battery, how would you break up such a battery such that you could bottom balance it with an available RC charger like you do? With used cells the more cells in p-groups the better (e.g. 13s10p). The two 8S mentioned at ES are ... https://www.am...
by eMark
Sep 13 2022 12:17pm
Forum: Battery Technology
Topic: one cell group wont fully charge
Replies: 78
Views: 1070

Re: one cell group wont fully charge

Following is relevant to those interested in tracking performance of a DIY build with used cells needing attention. Thanks Mark. ... How often do you take your batteries apart and bottom balance the parallel cells? Don't need to take apart when using my RC 6S Charger. But do need to be able to spli...
by eMark
Sep 12 2022 6:55pm
Forum: Battery Technology
Topic: one cell group wont fully charge
Replies: 78
Views: 1070

Re: one cell group wont fully charge

Side note: Just before the OP clarified with the post above mine, I found the site the OP noted https://www.repackr.com/ that is specifically designed to help use recycled cells of different capacities together in a "new" pack together. Believe m3vuv was as thorough as thorough can be in ...
by eMark
Sep 12 2022 2:39pm
Forum: Battery Technology
Topic: one cell group wont fully charge
Replies: 78
Views: 1070

Re: one cell group wont fully charge

Don't know if you even had time to read my previous reply to your question (with pace of reples) about a parallel group being affected by the voltage of another parallel group so will post again in cas other didn't read it ... Once got distracted a couple days ago while charging one p-group sufferin...
by eMark
Sep 12 2022 2:04pm
Forum: Battery Technology
Topic: one cell group wont fully charge
Replies: 78
Views: 1070

Re: one cell group wont fully charge

Top balancing is most common only because of a BMS whose balancing ability is questionable. You could call a BMS a lazy man's way to "hopefully'' balance a pack of good cells. Even though we all know that it's inefficient taking a long time to balance a pack (if ever) of used cells of questiona...