Duq

Rechargeable battery alternatives

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Now that the last handful of PF rechargeable battery packs are selling for silly money on BL I'm looking for an alternative for my next train. If it's not going to be original, then I might as well go for a battery pack with a shape and/or size that's easier to hide inside a steam engine. I've seen BuWizz but that's still expensive and includes a controller I don't need (because I already have Pfx bricks).

Does anyone have experience with third party rechargeable battery packs like the ones that go into RC cars?

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The easy thing would be to power the PF motors and IR receiver with an adapter cable to your choice of rechargeable batteries type.  Be it  AAA or AA batteries in a 6 cell battery holder or LiPO packs.

If you want to do LiPO, 2S LiPO batteries come in various sizes to meet your space requirements or runtime needs.  It would be a good idea to add a battery protection circuit to prevent damage to the LiPO from overdischarging and overcharging.

 

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That's the kind of info I'm looking for - what are decent brands for LiPo batteries, and what sort of extra electronics would I need?

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I had a chat with @raised just a moment ago about using a 9V block. He has some experience with it, and I now ordered a charger and some 9V 780 mAh batteries. The benefit for me is that I can just use the LEGO 9V battery holder which I'll connect to an Sbrick.

I'd be willing to sell you my PF LiPo for a decent price.

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I just use rechargeable batteries in the standard TLG battery boxes.  Do you have remove the battery's from box to charge but not to horribly difficult.  

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I did a small article on exactly this end of last year over at BMR; https://brickmodelrailroader.com/index.php/2019/08/21/alternatives-to-the-lipo-battery-box/

I'm currently both using 9v lipo blocks (works like a charm with pfx brick) and Chinese lipos. Just watch out with charging the latter ones, sometimes the load chips that prevent overloading aren't working properly, which already resulted in a burning battery of one of my fellow LUG members during an event last year...

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The short article on BMR raises (no pun intended) the questions but doesn't answer them. It does point to a thread here on EB that my search somehow didn't find (yes, I did search before starting a new thread...)

I'm not much of a purist (anymore) so I'd have no problem with third party LiPo packs and I'm handy enough to put something together and wire it up but... despite studying electronic engineering in a previous life I've no idea what sort of circuits would be needed.

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3 hours ago, Duq said:

The short article on BMR raises (no pun intended) the questions but doesn't answer them. It does point to a thread here on EB that my search somehow didn't find (yes, I did search before starting a new thread...)

I'm not much of a purist (anymore) so I'd have no problem with third party LiPo packs and I'm handy enough to put something together and wire it up but... despite studying electronic engineering in a previous life I've no idea what sort of circuits would be needed.

I have used these, with a custom adapter made of a 9V battery adapter (from my local electronics store) and part of a PF extension cable as a battery pack, and they last remarkably long: https://www.amazon.com/gp/product/B07BT4D99D

61-Z7K5Iw+L._AC_SL1000_.jpg

Edited by Phil B

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I'm using a similar battery, but with inbuilt micro-USB connection. All the protection circuitry is built-in, but the capacity is obviously a little less, 650 mAh. The battery doesn't need to be removed for charging in my little Koef 2 shunter.

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I recently ordered a couple of these USB-C/PD to 9V adapters with the idea that I could then use a standard battery bank (a newer one that supports USB-PD) to power the train.  I haven't ordered a battery yet so I can't give any recommendations there, but the adapter worked perfectly when plugged into a wall charger.

As a bonus, the adapter is really tiny, much smaller than I thought it would be from the picture, so it should fit just about anywhere.  I measure it at 11mm x 19mm.

 

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9 hours ago, TrainDragon said:

I recently ordered a couple of these USB-C/PD to 9V adapters with the idea that I could then use a standard battery bank (a newer one that supports USB-PD) to power the train.  I haven't ordered a battery yet so I can't give any recommendations there, but the adapter worked perfectly when plugged into a wall charger.

Excellent find! I had often wished USB chargers went beyond 5v since that could solve a lot of problems with off the shelf batteries. Turns out USB-PD does that. Looks like Qualcomm Quick Charge does too (my quick learning curve). Just need a battery that is within 16mm x 27mm x ??? to comfortably fit in a 4 wide hood. Keep us posted how your experiments proceed.

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You can go wider than 16mm if you can use panels for the walls of the hood.

I'm looking for battery packs to fit inside steam engines...

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On 4/20/2020 at 9:17 PM, Phil B said:

I have used these, with a custom adapter made of a 9V battery adapter (from my local electronics store) and part of a PF extension cable as a battery pack, and they last remarkably long: https://www.amazon.com/gp/product/B07BT4D99D

61-Z7K5Iw+L._AC_SL1000_.jpg

This looks like a great alternative to use with the old 9 volt battery box  4760c01 . 

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13 hours ago, zephyr1934 said:

Excellent find! I had often wished USB chargers went beyond 5v since that could solve a lot of problems with off the shelf batteries. Turns out USB-PD does that. Looks like Qualcomm Quick Charge does too (my quick learning curve). Just need a battery that is within 16mm x 27mm x ??? to comfortably fit in a 4 wide hood. Keep us posted how your experiments proceed.

I don't think we'll find much in the way of chargers that narrow, unfortunately.  The market is dominated by 18650 cells, which are 18mm diameter x 65mm length.  So probably the narrowest you'll ever find will be 18mm + a bit of case, so maybe 20-22mm?  That would still fit in a 3-stud-wide space, so could be feasible for some designs.

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On 4/20/2020 at 9:17 PM, Phil B said:

I have used these, with a custom adapter made of a 9V battery adapter (from my local electronics store) and part of a PF extension cable as a battery pack, and they last remarkably long: https://www.amazon.com/gp/product/B07BT4D99D

 

@Phil B, how is the power from these?  I have played with a couple of LiPo "9V" batteries.  One type worked fairly well, and the other was seemingly unable to provide sufficient amperage -- the train was very weak and sluggish with that battery.

I've ordered two more of the brand that worked well, but they're coming from China so that'll be quite a while...

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4 hours ago, TrainDragon said:

@Phil B, how is the power from these?  I have played with a couple of LiPo "9V" batteries.  One type worked fairly well, and the other was seemingly unable to provide sufficient amperage -- the train was very weak and sluggish with that battery.

I've ordered two more of the brand that worked well, but they're coming from China so that'll be quite a while...

I picked these specifically because the Amazon feedback indicated they provided the power they stated they would provide, and their claims about upgraded voltage (8.7V) seem correct. I have used the battery in my tiny DB Class V 36 engine and it works very well there combined with an old 9V motor. That said, the engine has issues pulling more than 2-3 large heavy carriages, but I attribute this more to the 9V motor and the gearing than to the battery. Battery is still on its first charge and has put in several hours of work. No endurance testing done however. I might switch it over to my Maersk and let it run for a while ... once I take my trains back out of their boxes (I just packed them up). That won't be for another few weeks.

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45 minutes ago, Duq said:

Those 9V blocks look interesting, much higher capacity than I'd seen sofar. Amazon UK has a similar pack:

https://www.amazon.co.uk/Rechargeable-Keenstone-Lithium-ion-Self-Discharge-High-Energy-Density-3-Pack

Should get it in a week or so, will post findings here.

Those Keenstone ones look similar (Btw, your link is not complete, this is the full link: https://www.amazon.co.uk/Rechargeable-Keenstone-Lithium-ion-Self-Discharge-High-Energy-Density-3-Pack/dp/B083J2G1NN/) but they are outputting slightly less voltage (8.4V vs 8.7V in mine). This listing is for an 8.7V 9V PP3 block: https://www.amazon.co.uk/Kratax-Rechargeable-Multimeter-Microphone-Protection-battery-charger/dp/B082CQSZ86/

Here is a picture of how I am using the 9V block:

49074600288_ffea2f4d82_b.jpg

I wrapped it in black electrical tape so its garish colors don't shine through gaps in the body of my engine. The great thing is that these 9V blocks have nice LEGO proportions, they are almost exactly 7 x 3 x 2 studs (if you include the battery connector).

Edited by Phil B

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Thanks for the tip! Only it came too late - already ordered the Keenstones... I'll see how I get on with them, might buy your recommendation as well.

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On 4/27/2020 at 6:17 PM, Duq said:

Thanks for the tip! Only it came too late - already ordered the Keenstones... I'll see how I get on with them, might buy your recommendation as well.

I hate to resurrect a 2-month-old thread, but have you been able to test them yet? I've recently bodged a 9V battery clip into an IR receiver's plug, and am now looking to buy suitable rechargeables to power things.

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Wow, they released a whole line of clone PF elements. Presumably bought in bulk from China. Still, if the battery is safe/stable, that would be a cost effective alternative. It would be interesting to hear from people as the gain experience with this.

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1 hour ago, zephyr1934 said:

Wow, they released a whole line of clone PF elements. Presumably bought in bulk from China. Still, if the battery is safe/stable, that would be a cost effective alternative. It would be interesting to hear from people as the gain experience with this.

If not, they will be in a lot of trouble as they are based in Germany and operate under EU law :grin:

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First thing of note to me is that the Bluebrixx battery is advertised as having a 500mAh capacity, whereas the LEGO PF Rechargeable was 1100mAh.

While I definitely love the concept of a third-party filling the Rechargables void, less than half the capacity/run time is just not a sacrifice I'm willing to make.

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