Endless Sphere

Please go on the youtubes and watch some videos on beginner level electronics and multimeter use. Dont ask on a forum to expect people to type out a beginners guide to electronics for you. Put some effort in yourself first.

They do the same trick that apple uses. When it sees a fast charger it will ignore the current limit and look strickly at temperature. Will will pump in current (up to 5A!) Into the cell and only dial it back to keep the cell from exploding. About 55 degrees. Only 5 degrees from critical. Great for ...

The english app works fine. Just enterr the right number and hit set. Didnt have any issues so far.

I got something like this but I need a professional machine with air pressure driving the head to push down at the tab You can buy those from a few companies. I have contacted a couple in the past for this but pricing was not worth it. You are looking at 2k and up for the whole machine and 700+ for...

dont, those headway cells are crap. no way they still work after 6 months in a 1P setup. better: https://www.ev-power.eu/LiFeYPO4-batteries-12V-1-1/Lithium-Battery-12V-60Ah-WB-LP12V60AH.html#tab2 this has the grunt to actually get the motor turning. the current while cranking might be 100~150A but t...

https://malectrics.eu/product/diy-arduino-battery-spot-welder-prebuilt-kit-v3/ only needs a car battery and if you make your own cables from 16mil you can use 1M long cables. i use this and have the unit and battery above the work area on a little shelf. i can weld basicaly up to 1.5M wide packs in ...

yeah, i think you lost me there. i am talking about cycling cells, not what to have for lunch.

I just posted margined estimates on how long I thought non-accelerated aging would take (at a given C rate which directly relates to hours), and the means of accelerated aging I was thinking of would be extreme thermal cycling under vibration load - on top of the electrical cycling at whatever rate...

there is no difference as far as i can see. the newer boards have SMD balance resistors and thermal band on them instead of tru hole resistors. that is the only difference. the chargery BMS looks (and is) more expensive, has a higher balance current but not much more. probably a bit more accurate at...

why?

its simple: just charge as slow as you can you can't charge a cell up too slowly. slower is better. even tesla nerfs the battery charge rates if you use the supercharger too much. i am working on this right now: https://endless-sphere.com/forums/viewtopic.php?f=14&t=93989 charging takes about 4~5 ho...

for the record: in 2 weeks i will take the system offline to install a UPS to keep the server and tester running when shit happens. data is automatically stored but its too much hassle.
UPS will be driven by a nice WAY oversized (lithium) battery.

sorry but no, physics dont work that way. (not exactly anyway) doing a 20C does not mean the cell lasts 20 times shorter then a 1C rate. just like running a engine at redline does not make it last half as long as when it runs at half the rpm it can. same goes with cell chemistry, doesnt matter if it...

i have destroyed 2 of those 709's. never again. i modded them quite to the extreme (lots of cooling on the transformer and much better connections and wire) but they still blew. use a dremel 85422 or 8215, those work best and really fast. dont forget to blow out any metal dust from the inside edge o...

of course you can use whatever reference test you want for capacity, as long as it is repeatable. but since most manufacturers have adopted the 0.2C discharge rate as the defacto standard ,anything different means you will not be able to compare to any other test data, only your own there lies the ...

bonus tip: also make sure you cover the entire cell with strip. it should not be possible to see the positive end of the cell. you can see you only cover half of the left bottom cell for example. also make the parralel strips longer so it goes over the side by about an inch. that way you can attach ...

You can set the acceleration buildup and torque times in the control software. Same for regeneration buildup. You can set them all to 1ms but then its virturally undrivable at huge power settings. Messing with the trottle range and mid point is more effective. Setting the first 70% of the trottle to...

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 an...

i have begun my testing with 4 NCR18650PF's and 4 NCR18650GA's. each group has the following loads: 4.2>3 at 2A discharge and .7A charge 4.1>3 at 2A discharge and .7A charge 4.05>3 at 2A discharge and .7A charge 4.05>3 at 3A discharge and .7A charge anyone willing to place bets when and wich one hit...

Better. But use a dremel to get rid of the weld spots on the cells before putting on new strips next time you reuse cells.

You are at the limit of the welder. I had the same issues and when the second one blew up (again) i got a different type of welder.

Just charge the all cells manually. If you got a unused powerbank in a drawer you can remove the board and connect that to the cells and charge each group individually with a usb cable. Not fast but works and you are automatically perfectly balanced again. But keep checking the cells, i expect they ...

what are you going to use it for? charging or running a motor or something? might want to check here: https://www.aliexpress.com/store/product/SD13TP-ZM-Outdoor-waterproof-connector-connector-4-pin-plugs-and-socket-Plastic-Circular-Waterproof-Connector/2411052_32729139263.html 1 size down but if you...

it depends on the manufacuters rating of the connector. some have a per pin current rating and others have a combined rating, yo see this a lot in the "oriental markets" to boost their ratings. i think 10A sustained in that cheap 4 pin connector is pushing it. it will get hot and in due time it will...

you can but they will melt, especially the fake ones you get from china.
5A limit is 5A limit. it does not matter what the voltage is.
also if you are going that route you need to use all the pins so double or triple up.

rg12 wrote: ↑

Jun 18, 2018 1:39 pm

flippy wrote: ↑

Jun 18, 2018 12:29 pm

the H is not isolated.
and yes, 96V nominal means 120V max voltage. so 28S max series battery.

Thanks alot but what does not isolated mean? you mean water proof level?

ask kelly, it is a engeneering term so it depends on what they mean by that.