SMC vs Zeee vs Lishen batteries heavy load test and internal resistance measurements 

Thank you!

Thanks, Jeffrey.

Awesome, thank you!

Pretty much. The LTO cells are expensive - I bought 60 of them for about $1,500. They're hard to find in stock, too. I use 24-26 in my "sledgehammer" electric turbo setup, depending on where I want the SOC - if you haven't seen it, here it is making about 722 hp at the drag strip: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-nlTVHkfSQXM.html But, you're correct - not everyone needs max power delivery. It's important to me for my electric turbo projects; but for others, size, weight or price may be more important. Which is why I included that data.

Yeah, I really need to get on that. Maybe a good video to make while I'm setting up and finishing out the new place.

That's a good point. I'd imagine the relationship would be pretty linear. So if there was a 4 volt voltage drop at 500 amps, you'd have a 2 volt voltage drop at 250 amps. BTW, the starting voltage doesn't matter - the voltage drop is purely current dependent.

Thanks. Yeah, I'm searching for the smallest/lightest packs, but the advantages of LTO are hard to ignore.

I'm going to try to do a video on exactly that. Thanks!

Lol. Most likely, the higher voltage pack would try to charge the lower voltage pack, but there'd be no current limiting aside from internal resistances. So you'd probably see about 250 amps instantly; or even more for a few milliseconds - big sparks.

@@AlexLTDLX Well, it could be done if the packs were managed by the same BMS at the cell level with an identical layout, but given that they are different chemistries, i really wouldn't do it lol. Sometimes, e-bike people will run packs in parallel, but they are identical packs. Even 0.1v of difference would make for huge currents.

It becomes a portable welder 😂

Thanks.

That's how Tesla does its "Ludicrous mode" too. In fact, in the drag and dyno testing of the electric turbo, the second pull always made more power than the first; at least until we switched to the LTO cells.

@@AlexLTDLX 👍👍. LTO are way more stable. If you run heated lipo batteries in parallel,should beat the LTO cells but very volatile

Thanks. Actually, that's kind what I've been doing when I was using them in the first electric turbo setup. They perform how you'd expect - with about half the voltage drop. Here's the video of that drag test at a private airstrip: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-AOL3Qyczt3Y.html

@@AlexLTDLX very kool. Thank you 😯

I do want to do a video on that - since c ratings seem to mean different things to different manufacturers.

@@AlexLTDLX do China lipo comparisons to with spektrum and other easily accessible batt. The market offers. I'd be willing to donate some for this video if needed and I'm sure many other followers would be willing for such a video. Might also consider affiliate links on a video like this and your attention to detail🤗

I would love to do that - and I probably will. I'm in the process of moving (it's a bit of a long process, since it's over 1,600 miles and I'm building the new place), but I should be situated sometime this summer. Then I'll set up a PO box and I'll be happy to test whatever people send me. Thanks for watching, commenting and the kind offer! Here's a video on the new place, in case you haven't seen it: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-8Jvj5RCvxSM.html

Well, the packs came with EC5 connectors and that's how they'd be used. But I have measured the resistance of most RC connectors in another video: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE--jLcgRxIfG8.html The connectors, along with the short length of cable, are responsible for about 0.25 volt drop.

I get nervous that things are going to blow up/catch fire. When they don't, the post-stress seems to come out in goofy ways...

@@AlexLTDLX I've twice had the unfortunate experience of plugging two LiFe 4s packs positive to negative before in my hands. You get that split decision to try and rip the leads apart as they are rapidly heating up. If you're lucky, the battery tabs evaporate.

Wow. I'm glad I didn't try it - I'm glad things didn't get ugly for you.

You would probably need to use 2 units given the current limits of available motors and ESCs to do that. The Speedmaster P2 supercharger is the way to go - dollar for dollar, it's tough to beat.

It's a moving blanket. And it's ok. I'm moving... lol.

How can I get my hands on that Onyx pack to test?

Most likely, I'll start small - getting someone local with a good fit car-wise. And then eventually perhaps I'll sell "modules" - compressors, ESCs, packs, etc. But honestly, I'm just having fun doing this.

The LTOs aren't a great option for an automotive battery. LiFePo4 is the chemistry your want - 4 cells are perfect. I built a 100 ah LiFePo4 batter for the LTD (the race car - this one: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-nlTVHkfSQXM.html) and it's been working great since I put it in - way, way better than the lead acid battery it replaced. Here's a video on it: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-cS1aQJOnqTQ.html

Voltage is Voltage doesn't matter how much restriction in circuit voltage will still be present. Not to mention a restriction will add resistance in return less current draw in return less voltage drop. In return the SMC lipos handle more of a load then the zee lipos.

@@KiloWattRC That's not correct. Voltage dropped over the connector.

@@timjs1018 the connector is not a load. Look into basic electrical. The Zee lipos couldn't handle the amp load and that's why voltage dropped

@DISHDOCTOR Everything with resistance is a "load" and voltage drops proportionally across it. This power is lost as waste heat, hence the very high connector temperatures he had after the test. I suggest you take your own advice and read up on basic electrical.

@@timjs1018 what u think the ec5 measures out 10 ohms? You won't loose voltage across the connector. Connector did just fine connecting path to ground, zee lipo had a hard time supplying 500amps for 5 seconds vs the higher true C rate SMC SRD pack

I haven't. But some others have with less than great results.

Actually, yeah, the shakes do get worse when I'm excited about something; but it's a medical condition known as "essential tremor." It runs in my family; I have a cousin with MS. Believe me, I wish that wasn't the case and it is something I'm a bit self-conscious of. And I did notice in editing how close the ruler looked to the pack in the video, but it wasn't in reality. I actually have a plastic ruler I'd usually use, but it's be hard to read on video. If it makes you feel better, the backside of the metal ruler is covered with cork. And I have dropped a busbar into a Lishen LTO pack before - I think there's a shot of it in the building of the "ultimate 12s pack" video.

@@AlexLTDLX Hey mate, you obviously have found a way to live and deal with what you have been dealt, keep it up. Yeah, my first trade was electrical engineering building switchboards and not your little domestic turds either, our boards started at several hundred amps (Aus, 240V, no 120v crap here) out to kiloamps in HV so a healthy respect for what you where using around potential energy was always on my mind. One of our reps put a stainless ruler to close to a set of enrgised 3-phase bus-bars and copped 70% coverage, 3 degree burns. Hard lesson.

For short bursts they'll hold up ok for a little while at least - but there is quite a bit of variation between Lipo brands - and these bursts are where the major differences will show up. For my purposes I need to know what these will do at very high amp draw. I have yet to find anything that can match the Lishens, though.