Search results

  1. parametrek

    LiFePO4 dead cell recovery

    The only way to answer those questions is to measure the cells. It can't be easily predicted because so much matters on the duration. Do you have an analyzing charger that could do a capacity test? With that you'll be able to see exactly how much capacity was lost. And by knowing the lost...
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    18650 batteries in bulk

    I assume you are in the US? There are several that are trusted by the community. 18650 Battery Store / Bulk Battery (same company) IMR Batteries Li-Ion Wholesale Batteryspace I've got most of their inventory in the bulk battery database for easy comparison shopping.
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    The radioactive diamond battery that can last 28,000 years

    Here is a debunking: While not completely physically impossible it is completely impractical for cost and safety reasons.
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    Travel charger for li-ion and NiMH?

    The Olight UC is the most compact charger but lacks the powerbank feature. The Armytek Handy C1 Pro is similar to the F1 and also does NiMH.
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    List of reputable Li-Ion sellers.

    My battery database tracks the inventories of all the US sellers that are considered trustworthy and respectable by several communities. These include: 18650 Battery Store BulkBattery Illumn IMR Batteries Li-Ion Wholesale Mountain Electronics Orbtronic RTD Vapor Vruzend The...
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    Shortest length protected 14500 button tops?

    Consider emailing Illumn. They have the NL1475R in stock and would probably measure it for you.
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    Seeking the best 18650 batteries available on Amazon US store

    2nding the advice to avoid amazon and purchase from a solid vendor. A store that is geographically close to you might save some shipping time too. Here are all the most trustworthy vendors and where they ship from: Illumn (CA) Mountain Electronics (UT) IMR Batteries (TX) Vruzend (FL) Li...
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    nuclear batteries with diamonds

    It has been thoroughly debunked: I am not sure why it is making the rounds on the tech news sites again. Nothing has changed since January when it went around the 1st time.
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    IMR or protected li ion?

    Looking through my battery database the available selection of protected 16340 is a little slim. RTD Vapor has a great price on an 850mAh cell though. If you want belt and suspenders there is a protected IMR cell out there. It is a 650mAh Xtar at IMR Batteriers.
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    Externally powered battery charger?

    No internal circuitry at all? Like just a spring loaded bay with some wires coming off of it? I've seen those on Aliexpress. They are usually sold as battery testing gear and will have connections for 4 wire kelvin sensing. I believe HKJ has written about them in his descriptions of his...
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    effects of using 1.2v NiMH and 1.5v Alkaline in series?

    In series strings the cell with the lowest capacity (amp hours) will be drained dead 1st. Past that it will be driven into negative voltages as the other cells try to force power through it. This can happen at any load. There is a special case under high loads. Here the cell with a highest...
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    CCCV Charging of NiMH Cells

    I was under the impression that there is a lot of CC-CV NiMH charging done out there. I've heard it referred to as "bulk" charging and can get up to around 70% of the capacity. Going higher requires dV/dt termination. This is why Eneloops are "precharged to 70%" because they can safely do it...
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    Time to adapt the 21700 standard

    I guess etc didn't like the way that this forum was replying to him. Lynx Arc nailed the biggest issue. Tesla can make whatever size battery they want because they have their own factories. The size of the battery is proportional to how much cooling they need. As the chemistry improves and...
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    Time to adapt the 21700 standard

    People still use AA and AAA lights despite 18650 existing. Size matters. So far all of the big OEMs have been making both 18650 and 21700 cells using their latest and greatest processes. As long as that continues there will be no strong advantage to either. On the hobbyist side of things...
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    USB magnetic charger for Eneloops

    The Olight UC is the best option that I know of.
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    List of reputable battery retailers?

    I keep a list of all of the li-ion battery vendors in the US and europe that various communities (flashlight ebike vape etc) trust. But I guess I can't share it.
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    I don't trust Orbtronic anymore, what else should I use?

    That is a shame. The were basically the 1st people selling 18650s to us normal folk. I've compiled a searchable database of every major vendor's inventory of 18650s. (See sig.) Illumn is a particularly good vendor. The current favorites for high capacity 18650s are the LG MJ1 or Panasonic...
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    PowerX Pro Lasting me 5x longer than Eneloop Pro now!

    Peter - do you happen to work for LLoyds selling PPI?
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    New Streamlight lantern came with Chinese 18650 battery - safe to use?

    The vast majority of Chinese li-ion is perfectly fine. They make lots of respectable batteries. There will always be scumbags at the bottom trying to make a quick buck and selling junk. These are the batteries that make the news. But Streamlight will have done their due diligence and will...
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    Recommened LiION AA ?

    You do not want any of those. They are all junk compared to normal NiMH low self discharge Eneloops.