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  1. E

    In-situ 18650 heater cell detection

    Yes it would. The PCB I designed fits a 4x5 cell holder so for 80p you can just attach 4 of those side-by-side to a single block. The part that is currently missing is a "master" microcontroller that can aggregate the temperature readings from 4 separate sensing boards.
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    Recyclable Lithium Box, lets you build batteries in 15 minutes. Crowdfunding technology

    Have you measured the additional internal resistance introduced by a purely mechanical contact between a cell and busbars? I did some experiments on this and measured that when I used spring contacts like these: https://www.aliexpress.com/item/32884289489.html this added around 100 mOhms to the...
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    Alternative sources for 18650 nickel sheets with integrated fuses

    Does anyone know of any way that batteryhookup's 18650 nickel sheets with integrated fuses can be bought from within EU? Ordering those from US has ridiculous shipping costs and considerable shipping time. Also are there any alternative manufacturers of nickel sheets with fuses integrated that I...
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    batteryhookup nickel fuse

    In order to protect from the situation where you accidentally draw 5 amps from each cell (not blowing the per-cell nickel fuse) which gives 400 amps for a 80p block (melting your busbars in the process) you need to have a fuse on the entire block (or the entire string) limiting the current to...
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    In-situ 18650 heater cell detection

    That could also work if there would be a way to reliably provide thermal contact between the sensor and 4 adjacent cells. There is a significant amount of space there, maybe you could wrap the sensor in something like some kind of heat-conducting compressible foam or smth :).
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    In-situ 18650 heater cell detection

    One of the threads on this forum (I lost the link) from hbpowerwall where he reported a pack suffering a major failure with one of the cells going thermal runaway. My hypothesis is that this doesn't happen suddenly but would be preceeded by abnormal heat generation from a single cell as the...
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    In-situ 18650 heater cell detection

    I know LM35 but it outputs a voltage which would require additional hardware for me to read (analog mux, adc, etc.). For an experimental setup using sensors which have a I2C bus was quicker to prototype. For a production device I will need to consider the BOM cost of having a bunch of simple...
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    In-situ 18650 heater cell detection

    1 Introduction This is the documentation of some experiments I performed in order to ascertain whether it's possible to detect cells generating excessive heat (aka "heaters") in a diy 18650 battery pack built using the popular 5x4 20.2 mm pitch 18650 cell holders. All of the findings should be...
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    Mounting 18650 cell packs on DIN rails

    I have not yet performed the experiments to establish an upper weight limit.
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    Mounting 18650 cell packs on DIN rails

    It is true that DIN rails are not designed for carrying very heavy loads. The quality of fastening of DIN rails to the base (ie. wall) will be critical in my opinion. Here you have two things to consider - first not all DIN rails are made equal, there exist flimsy and "heavy duty" DIN rails. The...
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    Mounting 18650 cell packs on DIN rails

    I wanted to share a 3d printed mounting bracket design that I made to mount 18650 cell packs on DIN rails. I believe this can be advantageous for diy powerwall builds because of the following factors: DIN rails are a standard industry component which can be easily purchased instead of ordering...
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    Consolidate Excel battery lists?

    Yes, this is correct. I have reverse engineered the protocol and LCD layout and created a PCB which you should be able to order on JLPCB for example. Unfortunately likely to design mistakes in the USB side the USB interface is very flakey (the host can't often read the USB descriptor properly)...
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    Zigbee protocol of Enecsys SMI-360-72 microinverter

    Hi everyone, I came in posession of a Enecsys SMI-360-72 microinverter which I would like to use in my setup. The inverter itself contains a Zigbee radio which is used to communicate with an Enecsys "gateway". All of this allows to monitor the inverter parameters and most likely do some setup...
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    Megacell Charger firmware V4.3.0.11 reboot loop

    Hi guys, I have been experiencing one of my Megacell Chargers rebooting in a loop and not being usable because of this. The symptoms are that the display shows "Display test" and the fw version, then the charger connects to wifi successfully and a message "Mc6 Init" appears at the bottom of the...
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    18650 Nickel Fuse connectors

    +1 for this question. The time and shipping costs from US are ridiculous when ordering this pretty basic part ;). Are there any suppliers in EU?
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    When things go wrong... it can go really wrong!

    Would you think it would be a good idea to implement per-cell MOSFET switches in order to cut off an overheating cell (or cells) if the temperature sensors detect an anomaly?
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    Not a newcomer but still

    Hi everyone, I have been lurking around this forum for a while now while gathering know-how and cells to get closer to diy electricity independence :). I don't remember how I found this forum, I believe it was related to HBPowerwall youtube channel. I have some of my related projects...
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    RC3563 IR tester

    Lol, this is crazy. You should be able to code something in VBScript or .NET maybe. Not my area of expertise though :).
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    RC3563 IR tester

    If you want something that's more geared towards workflow automation I wrote a simple python script that interprets the RC3563 protocol and prints it out in human readable form. https://gist.github.com/mgrela/e5e52e22e5d748645bf4d0ebe2c133dd
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