So far, no such luck and I ordered the blessed thing pretty much for this reason.

What I can guess and see is they have an ever so slightly larger positive post on them than anything else I have around.

Swap the old weak Duracell in, get the green light.

Swap fresh, new and charged Eneloops in and no green light. Also the eneloop triple AAA are only 1.2v and this is the problem period, but Lego even says lower voltage will only affect speed(this is common among rechargeable batteries).

Anyone else run into this?

Noticed it earlier and actually took the battery box apart and from what I could tell inserted one at a time it seemed to do fine as far as contact went and you could see the metal contacts flex slightly.

Might be coming apart again to wallow out the holes a bit for battery contact.

Anyone else been here done that?

Need to get it fixed before Wedns. afternoon, he gets his train back if he is good in school. Not making a good living for the battery companies on triple AAA's would be appreciated.

Edited January 14, 201411 yr by v6TransAM

With NiMH rechargeables, I get same issues every now and then. I try rolling the batteries in the holder. Some times that work. If not, I take out the batteries and re-insert.

I've been using Eneloops in my trains for a couple months now, and have been very happy with them.

Maybe the charger is your problem? I got an awesome one from a company named 'La Crosse' off Amazon for less than $30. It's a huge step up from the basic chargers I've had. I'd never ever use another charger again, it's that good.

Joe

Batteries aren't quite making contact. Her and I were screwing around with it a bit. The positive end has a slightly larger shoulder on it. Hangs up on the plastic ever so slightly.

Tried the rolling, reinserting, poking, prodding, etc(we still talking about batteries? ). Nothing seemed to matter but looking at it with a Duracell and an Eneloop in there and it looks like that shoulder is just hanging up.

I did test the batteries in something else when I got them in and again after I charged them.

Hmmmmm, now do I dress the positive of the battery or disassemble the battery box again and slightly ream the holes out so it contacts the metal........?

Well, I've certainly poked and prodded a lot in my day, and struggled with batteries as well, but never had issues with Lego battery boxes like that. I'm always very careful when I take the batteries out of the case (with a small screwdriver) as I don't want to damage anything.

If it's not going to work maybe it's time for either a new battery box and/or batteries? I know what we're discussing here is small, but perhaps photos would help us help you?

Joe

You could take apart the battery box and enlarge the opening in the plastic. Measure the diameter of the battery's positive terminal and make hole slightly bigger. That's probably the easiest to do. If you're good with soldering, you could try to build up a layer of solder on the contacts so it reaches the battery tips.

I exclusively use Eneloops in my trains, and I frequently have issues with the batteries making initial contact in the battery box. Removing and putting back each battery, trying to turn on the battery box between each, seems to fix the problem. Typically its the batteries closest to the top of the box, but I've experienced issues with all six compartments over the years.

--Tony

I use Eneloops in every single one of my trains and remote controls.

I am going to tackle this later today at some point. I am currently thinking enlarging openings will be the easiest route, just hate taking apart the darn battery case again. got to find the set of jewelers screwdrivers I have around here lol

Will also try and take some pics for it as well

I don't screw in the battery case. Half the time I leave it completely off, the batteries don't care.

--Tony

Look closely at the top of the batteries, Eneloop is more upright and round, the Eveready is more rolled over towards a tip. Duracell literally come to a point on top of the battery.

This is what you start with as you get it from Lego. Notice the round holes on positive end are very small compared to the positive ends of the batteries?

You can see where the problem lies; the small hole as well as the contact strip being inside of it nearly completely.

How do you fix this? Take off the battery cover, then remove the four screws holding the secondary cover on the case. Be careful and work slowly since it is tight and there are wires present.

You will need the following:

Small philips screwdriver

Fluke or equivalent electrical meter

7/16 drill bit

3/8 drill bit

X-Acto or razor knife/hobby knife

This is what it will look like after you ream out the holes slightly with the 7/16 bit(by hand). I do recommend keeping pressure/finger on the outside of the contact while reaming. Your worst case scenario here is you break the small melted plastic pin holding down the contact strips. It would be easy to fix with a hot glue gun.

This is what the center battery holder positive terminal will look like after reaming. Put the 3/8 bit across the case and use it to keep the 7/16 your using to do the reaming(by hand) with located more towards the top of the terminal hole.

Once you get this far, you can use the 3/8 drill bit(by hand) to clean up where you reamed out the holes with the 7/16 bit(by hand).

Then use the razor/hobby knife to clean it up and you will have to know or look real good to notice anything is different. I would have more and better pictures, but was doing this on my new laptop so some of it got jumbled up and lost.

Then, insert one battery at a time and test each one by using the meter on DC volts. Test it by using the metal contacts on the outside of the case. It should match the voltage you get just testing the battery with the meter. Remove battery and check the next set of terminals until you work your way thru all six holders and the numbers on the outside of the case match what you tested the battery as. If you feel that any of the terminals are in danger of coming loose from the plastic pins, a hot glue gun will be your best friend. If I have any issues with mine I will do it for some reinforcement, they are kind of cheaply made, if you take one apart you will see it as well.

This will cure ANY fiddling with batteries that you had to do before the modification including in the future. It will be done on any future PF battery boxes my son or I end up with(unless Lego see's this and does something about it)

Bottom line, I spent maybe 30 minutes total here from start to finish. End result is a happy dad and an ecstatic 3 year old who has his train back and running.

My question is, "Lego, why did I have to do this? You should modify the mold slightly so others do not have to."

First post with fix/mod, so I hope it seems decent enough for you guys.

Edited January 18, 201411 yr by v6TransAM

Good work. I don't think the designers had Eneloop batteries when they designed and tested the box.

I think it might be possible to shave the plastic with a Dremel tool and engraving bit without having to take apart the battery box. But really steady hands are needed.

Could you instead find a right sized piece of conductive material like a small washer, piece of metal rod, or even a ball of tinfoil to bridge the unmodified gap?

Could you instead find a right sized piece of conductive material like a small washer, piece of metal rod, or even a ball of tinfoil to bridge the unmodified gap?

I would not waste my time with that, nor trying to build up solder. Just open it up a little and never have an issue again.

As far as the Eneloops go, they are on the larger side of things and more common in Europe/Asia than here, but Lego is a global company. I have about 5 different AAA batteries here, some caused issues and some did not. Duracell will not cause issues at all, with Eneloop seeming to be the most intrusive as far as bad conduct goes..

I like to fix things so they no longer cause an issue. I want to play Lego's with my son, not fight batteries in a poorly designed battery pack/case

PS Wish I did not delete the completed pics lol It does not look as ugly at all once done, the pics are from the first reaming with the bit

Edited January 18, 201411 yr by v6TransAM

Thanks for the pics and advice. I've not had any issues with Eneloops yet, but will have to pay closer attention next time I swap out the batteries.

Perhaps the blame lays with Eneloop for poor design rather than with Lego?

Joe

Thanks for the pics and advice. I've not had any issues with Eneloops yet, but will have to pay closer attention next time I swap out the batteries.

Perhaps the blame lays with Eneloop for poor design rather than with Lego?

Joe

I'm going all Lego on this one. I have used them in anything in the house that I could put AA, AAA or C or D with the adapters and they fit in every other device in the house, just not in the Lego battery pack.

The kid is happy now though and so am I.

Wow!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I am updating this because the Eneloop batteries finally tuckered out after a month of heavy duty use.

This is the first day I have had to remove and recharge the batteries since the original install in this thread.

28-29 days of use before recharging was necessary. They also outlasted the original Duracell I had installed as well by a weekish or so(Rayovacs were for pics)

Glad I bought another 8 for the cargo train I got for him on sale for his birthday next month.

Just thought I would share real battery info with you guys on here

Hey, that's great. I just get a couple days use out of mine, but the trains run a long time, and it's been very cold in the basement.

Joe

I don't screw in the battery case. Half the time I leave it completely off, the batteries don't care.

--Tony

This. I almost always put the cover back on, but never screw it in place. Thinking about it, the batteries sit in the box very tight; the cover is probably not all that necessary, period. Perhaps the cover would be important in a very humid climate and/or if using alkaline batteries?

For my purposes, the Rayovac NiMh rechargeables work fine (especially when Wal-Mart had them on clearance). I have a spare set on the chargers, so if whatever train we are running here dies, a quick swap gets the train back up and running. The Rayovacs are better than the Energizer NiMh, based on my experiences. Most of our PF trains are operated by a powered car (baggage, box car, combo, etc) with two PF motors. The Rayovacs pull many hours before a recharge is needed. Probably not nearly as long as the Eneloops (which sound very interesting!), but fine for the guy who runs trains for an hour so a day with his kids.

Some of our club members do use eneloop batteries, as far as I know there wasn't any trouble with them.