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    "Copper/nickel sandwich" buses for series connections

    Thanks for posting this... just found them on AliE from WELLGO (AliTools plugin is great for reverse image lookup). Is there any disadvantage to these over the sandwich technique? These seem to be perfect.
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    Can a basic CCCV power source be left connected to a Li-ion battery with BMS?

    Yes, I think they are likely a little beyond the scope and size of my project unfortunately!
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    Can a basic CCCV power source be left connected to a Li-ion battery with BMS?

    Thanks, all useful info. Circuit design is a little beyond me, even something relatively simple like this. So off the shelf stuff is much more appealing. I did find this blog post with freely available designs: MOSFET – IDEAL DIODE I may head to somewhere like Fiverr to get someone to look...
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    Can a basic CCCV power source be left connected to a Li-ion battery with BMS?

    @amberwolf (or anyone actually) Do you happen to know of a source where one can purchase a high quality ideal diode circuit? It's hard to tell the difference between the various ones on AliE, I would love to find someone making them with chips from Analog or TI or similar. It's also really...
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    Can a basic CCCV power source be left connected to a Li-ion battery with BMS?

    Yes, certainly planning on it (y) I think I almost certainly have space for a bigger BMS, so if this one isn't up to it I will choose something that is.
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    Can a basic CCCV power source be left connected to a Li-ion battery with BMS?

    Thanks, appreciate the vote of confidence, as I always worry I have missed something obvious! I have a load tested which can pull 600w on the way from AliE, so I'll test out the batteries at maximum drain. The Eve25p specs actually do say they can provide a max of 30a in the spec sheet, but...
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    Can a basic CCCV power source be left connected to a Li-ion battery with BMS?

    Thanks for the thorough replies. @harrisonpatm - I am planning to test the BMS when it arrives, set it's upper charge limit and check that if the power supply/charger exceeds this if it will correctly cut the power, I couldn't find any proper documentation for the BMS, so I was assuming this...
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    Can a basic CCCV power source be left connected to a Li-ion battery with BMS?

    I am looking to integrate a small 13s2p battery into a rackmount enclosure to act as a UPS. As such I would like to have this battery charging whenever other sources of power are connected. My basic plan was to use a JBD BMS and then a simple CCCV DCDC converter (RD RK6006) supplying it with...
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    Is the semi solid state claims from Chinese batteries true?

    I see, fair enough. Yea these 'semi-solid state' cells don't seem to be currently exceeding Li-Ion by much (I had used Samsung INR21700-50E for my project a while back, which are at around 260wh/kg) - but with the safety aspect as well as the cycle life increase they are certainly interesting...
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    Is the semi solid state claims from Chinese batteries true?

    Just bumping this fairly old topic to see if you ever made any progress?
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    Has Energus - Maker of Tiny BMS folded

    So just to answer my own question: They are still around and still selling their BMS, but looks like they have pivoted away from it as a business model. As mentioned their website redirects to enepaq, but their actual business has changed names to "GridUp", and www.gridup.com looks like it's...
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    Has Energus - Maker of Tiny BMS folded

    Their website (www.energusps.com) now redirects to www.enepaq.com Still seems to be based out of Lithuania, so perhaps they have just pivoted away from selling to end users? Just wondering if anyone has any more info.
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    Soldering with a spot welder...

    Well damn.... what if you reduced the joules to a level that was melting the solder but not flash frying the flux?
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    Soldering with a spot welder...

    Do you think that it would be significantly different to spot welding nickel direct? I know even this isn't 'ideal' - but by my thinking if you used solder under copper strip and hit it with a spot welder - if the solder flowed and made a good join then it's superior contact with a metal that...
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    Soldering with a spot welder...

    Given the attempts to find a way to get copper strip to work well as a DIY-able battery connect it got me wondering the question: What would happen if you place a wee blob of solder paste between cell and copper and then zapped with the spot welder? An initial google throws up someone who...
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    Battery Hookup 32650 (32700) LiFePo4 cells

    Anyone got any of these in to test at various C rates? They look awfully tempting at their $4 price point.
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    Any EU suppliers that can supply 6000mAh 32650?

    I have just seen BH's $4 32650 6000mAh cells, it's just about the best deal I have seen on new lifepo4 cells from a known reputable supplier. The price and weight bring it within sniffing distance of my Li-Ion build. It's still heavier, but only by about 15-20%, and as I was over-provisioning...
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    14S9P Samsung 50E battery pack build

    That's true, although OTOH a large heat sink may actually increase the burn temperature of the fuse. Not sure how easy Alu is to weld or solder. I know it's harder than steel to weld with an arc. Re your second paragraph: That's correct on a per individual cell basis, and as the P group is...
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    14S9P Samsung 50E battery pack build

    So I'm just bumping this as I think I may have got my thinking wrong on how much current each connection between P groups needs to carry. Or rather, I haven't got the total wrong, but the cals on the 'busbar' wrong. In the pic I posted, each bar that the cells are fused to needs to carry 80a+...
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    Cell level fusing - current failure requirements

    Thanks for your post, very helpful and more or less in line with my thoughts. My focus on Nickel was its weldability. You can solder nickel to a copper bus bar, but with the available spot welders copper doesn't play nice. My use case is also not a bike, I'm building my pack for portable...
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    Cell level fusing - current failure requirements

    Just wanted to check with the community knowledge if there is any reason for cell level fusing other than internal shorts? My thinking is that in this event the 'fuse' will deal with a huge current. Lets say in a 9p pack you are easily talking hundreds of amps (If I am correct to assume that in...
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    14S9P Samsung 50E battery pack build

    A previous topic I had covering my build went walkies so this is a new topic to check my thinking during my build. I have already had some super useful discussion in the aforementioned topic as well as doing plenty of reading on cell life and life cycling by the members here doing that testing...
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    Thread for new battery breakthrough PR releases

    Where did you get this info from? I can't find reference to it. Most articles cite a 3x increase. Over 1000Wh/Kg would be 4x or more, and a 'coin cell' would be substantially more than a 4x reduction to an 18650.
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    Topic vanished?

    Thanks for that, that was indeed the topic I was looking for - no idea why it was gone AWOL. Thanks for posting the copy here though, there is some useful stuff in there that will be good to refer back to.
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    Topic vanished?

    A topic I made with advice on what charger to use among other discussions about batteries has vanished - I really don't think it was breaking any rules but if so I didn't receive any kind of warning. I was just wondering if maybe it was something server-side?
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