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    • October 25, 2019 12:23 PM EDT
    • Bill Barnwell said:

      Will a 18.5 battery out last a 14.8 if both batteries are of the same mah, run the same engine at the same speed? Is it smart to purchase higher voltage batteries?  

      Bill, to run an engine at a specific speed requires a specific voltage, and that dictates what current (amps) the motor draws.  So if the engine is running at the same speed and the batteries have the same capacity to produce amps (milliampere-hours, or "mah",) then the maximum voltage is irrelevant.  The max allows your train to run faster, buit if the 'mah' are the same, it won't run any longer.

      That's my story until someone who understands this stuff properly jumps in.

    • October 25, 2019 11:34 AM EDT
    • Will a 18.5 battery out last a 14.8 if both batteries are of the same mah, run the same engine at the same speed? Is it smart to purchase higher voltage batteries?  

    • October 25, 2019 11:00 AM EDT
    • Either cell type, utilizes the same charger and charging algorithm with some caveats and require like care. Both cell types suffer from similar aging and or life cycles; generally the application, care and feeding dictate lifespan as well as the quality of the materials and assembly processes. My experience with thousands of lithium batteries suggests that they have similar life span cycles. Either cell types inherently have low self-discharge and do NOT require "priming". Lastly the life cycle clock starts as soon as the cells are assembled, used, stored and ignored matters not.

       

      I predominantly use Li-Po batteries for trains, planes, drones and RC cars/trucks and have realized zero pouch failures to date. There are many Li-Po batteries sold/equipped with plastic hard case shells to protect said pouches. Battery protection circuit boards with desirable additional features are readily available for Li-Po's if so desired. I use SMART balance charger features with both cell types and find it very informative (I assemble Li-Ion batteries and add balance charge pigtails to same).

       

      Li-Po's batteries are generally speaking much cheaper as compared to Li-Ion batteries of like capacity and voltages.

       

      I believe Lithium catastrophic battery failure modes are generally the FAULT of the operators interaction with the charger in play, the WRONG charger and or poor integration of said batteries. Dedicated use simple chargers (cell count/voltage specific) without the ability to change charging parameters provide a safer approach as compared to programable chargers. 

       

      Michael

       

       

       

       

       

       

       

    • October 24, 2019 10:20 PM EDT
    • it's not really the chargers, it's physical damage to the pack that causes the most problems.

      On chargers, get one that is set for your voltage and works with the amp hours. I prefer chargers that can be configured for different packs, but it's easy to make a mistake and charge wrong.

      Also, I don't really see the need for balancing chargers, we do not work our batteries hard like the airplane guys.

       

      Greg

    • October 24, 2019 5:23 PM EDT
    • Greg, thanks for the reply, I was more concerned about safety than anything else but the more I have read lipo seems to get a bad rap for bad chargers, and you are right about size. Right now I'm looking at a ion that is only 3.14" x 2.75" x .78"  which I might be able to fit in my tender section of my Mason Bogie and although it is only 3400 mah it might work with the small size of the gscale graphics railboss board and then it would all be onboard without having to use a trailing car, Thanks, Bill

    • October 24, 2019 3:36 PM EDT
    • Interesting, I have not seen any credible statement that li-ion ages and li-po does not.

       

      For our hobby, li-ion is usually found in cylindrical cells, and li-po is usually in a rectangular, somewhat flexible "pouch".... mechanical damage can result in fires, and the pouch is more easily damaged, so people typically recommend the li-ion in the "tougher" package.

       

      Bill, inferring from your builds, I think you should stick to combinations of the 18650 cells for your best price/performance. Not as space-efficient as the prismatic (rectangular) li-po, but usually a better choice in our hobby.

       

      Greg

    • October 24, 2019 12:31 PM EDT
    • Bill Barnwell said:

      Being new to battery power I have been reading up one batteries and would like LSC members thoughts on preference of ion batteries compared to lipo batteries and why. Thanks, Bill  

      Bill, my understanding is that LiPo batteries are just LiIon batteries in a different format (i.e. flat and rectangular to fit a laptop.)

       

      So I googled your question and I stand (mildly) corrected:

      "Lithium Ion Batteries have high energy-densities and cost less than lithium-polymer batteries. In addition, they do not require priming when first used and have a low self-discharge. However, lithium-ion batteries do suffer from aging – even when not in use. Varies, depending on electrolyte"

       

      My pal as a LiPo battery in one of his locos and it does not seem to exhibit any different characteristics than his LiIon.  Personally, I stick to LiIon for practical reasons - they come in fixed shapes (e.g. 18650 type), can be mounted in a battery box, and monitor/protection PC boards are easy to come by.

    • October 24, 2019 12:17 PM EDT
    • Being new to battery power I have been reading up one batteries and would like LSC members thoughts on preference of ion batteries compared to lipo batteries and why. Thanks, Bill  

    • October 24, 2019 11:25 AM EDT
    • removed too

    • October 24, 2019 11:19 AM EDT
    • removed

       

    • September 24, 2019 8:20 PM EDT
    • We could be wrong, but I'd exhaust that possibility first.

       

      Greg

    • September 24, 2019 6:52 PM EDT
    • Mike and Greg,

      thanks much for the input and insight. You have given what to focus in on

      thanks again——much appreciated

      chuck

    • September 24, 2019 6:46 PM EDT
    • Yep, I agree, that was the path I was headed down, I suspect a cell.

       

      Greg

    • September 24, 2019 10:57 AM EDT
    • I suspect the multiple comments shared above have more to do with suspect cells than PCB's and or chargers. In my experience with Lithium-Ion batteries. a single cell acting-up is the typical problem herein. The PCB reacts to over-under voltage thresholds at the least. Battery protection ICs typically use MOSFETs to switch cells in and out of circuit. Fancy and or smart chargers look at individual cells (if connected for balance charging) and or the battery/cells combined voltage, internal resistance and more. Accordingly cells that are suspect skew a monitored threshold and the charger recognizes a connection error, (said "connection error" is the result of the PCB opening the circuit). The charger may also shut down due to realizing voltage/current/time thresholds.

       

      In short if your able to rejuvenate a battery with a dumb charger, that a smart charger has issue with, suggests at least one bad cell is in play. Rejuvenating a problematic battery will inevitably result in a capacity reduction. 

       

      I've shared in previous posts over the years that single cell Lithium-Ion failures are not unusual and typically overlooked or ignored in batteries. Multi-cell batteries wired in parallel and especially high capacity batteries with sets of cells in series-parallel configuration to gain higher mAh ratings often have a suspect cell unbeknownst to the user. Load testing batteries will divulge this anomaly (accomplished by recording the static voltage and subsequently applying a two Amp load and noting the voltage therein). Generally the voltage will drop some, if the voltage drops sharply and or the volt meter goes blank and recovers after the load is removed, you have a problem. Smart chargers with cell balancing features, together with batteries with cell balance pigtails will monitor/expose a suspect cell while under charge.

       

      Michael 

    • September 23, 2019 3:49 PM EDT
    • It might be interesting to leave a voltmeter on the charger output, and see if the voltage varies when it says connection broken.

       

      Are you using the balancing connections?

       

      Greg

    • September 23, 2019 3:21 PM EDT
    • Chuck Agonis said:

      Thanks Jon. My thought was the pack needs replacing but not sure. I also thought it might be the charger?  But then it doesn’t happen on all battery packs

      I've seen similar events, especially on the packs I make myself.  The protection circuits seem to fail and do all kinds of weird things.

       

      But sometimes it's the charger.  My pal gave me 2 packs that wouldn't charge on his fancy charger, but they charge fine on mine!  I suggest trying a different charger, and a different protection board.

    • September 22, 2019 7:19 PM EDT
    • Thanks Jon. My thought was the pack needs replacing but not sure. I also thought it might be the charger?  But then it doesn’t happen on all battery packs

      thanks again for the response

    • September 22, 2019 7:09 PM EDT
    • I have an older LiIon pack that does th same thing. I think that means it's toast - but if I put it on the dumb charger it will cycle back and forth between charging and full =for several hours, then eventually be usable, but the capacity is reduced. My guess is that the protection circuit is breaking the connection for some reason.

    • September 22, 2019 7:04 PM EDT
    • I use battery power for my large scale locomotives.  4 pack Lipo cells charging using a Tenergy balanced charger/discharger. Occasionally I will get the “connection break” error message. So contact cleaner on the connections will help.  But what does it mean if the charger has already started in the charge cycle and has been charging for several minutes and then the “connection break” message occurs?  Contact cleaner and restarting the charge cycle and in about 2 minutes the error message occurs again. Does this indicate the battery pack is getting faulty and should be replaced?

    • September 18, 2019 12:42 PM EDT
    • Travis, I do have some stuff on PH hobbies... if you can show a picture of the board... maybe I can find something.

       

      Look on this page, maybe the bottom one?

       

      https://elmassian.com/index.php/large-scale-train-main-page/dcc-battery-rc-electronics/sound-systems/p-h-hobbies

       

      Greg