Why are Eneloop Pro batteries good?

[Technic Jim]

Hello all,

I am currently filming a fast car moc which uses two RC motors and a RC unit. It is quite quick but I don't think that it is running at its full power and speed. For instance, with fresh rechargeable 1.2V NiMH batteries (when fully charged they are 1.4V) it can only run downhill. The batteries are quite good high quality ones with 4 of them 2000Ma/H and two 2500Ma/H but they can't seem to power it well. I've heard that most people use Panasonic Eneloop Pro batteries but they are quite expensive. There are the standard eneloop batteries as well which are cheaper but probably not as good. What I don't understand is what is so good about the eneloop pro batteries. Do any of you know what makes them so good and is it worth buying some to use.

Thanks, Jim

[Blakbird]

When you are looking for max power, the main difference between batteries would be their maximum current. I don't know what the max current draw of the Eneloop batteries is, but it can't be any better than Nickel Metal Hydride. Those batteries can pull 20+ Amps. If you can't get it to work with NiMH's then I would suggest either your batteries are defective or you are asking too much of them.

[Technic Jim]

Is that the MaH rating - the higher the MaH, the quicker the motors

[RPABLOM]

Is that the MaH rating - the higher the MaH, the quicker the motors

i knew that MaH is the capacity of the battery, i have 12 2700 MaH bateries for my MOCs, but a standart duracell batery works way better (probably cause rechargable are 1,2V and regular are 1,5V

[Technic Jim]

What are the batteries called that you use and where did you get them from?

[Blakbird]

Is that the MaH rating - the higher the MaH, the quicker the motors

No, mAh is milliamp-hours and tells you the total capacity of the battery. It doesn't really have anything to do with the output power. A higher mAh does not mean quicker motors, it just means they will run for longer.

[Epic Technic]

I don't have any experience with Eneloop batteries but if your want to get better performance you could use three IMR batteries and three dummy batteries. Though this could damage your LEGO because of the over voltage (11.1 volts instead of 9 volts).

[roppie11]

i once read somewhere that lego uses 12v motors, so that it is hard to destroy them. i wouldn't use 11 volt though.

[Technic Jim]

I don't have any experience with Eneloop batteries but if your want to get better performance you could use three IMR batteries and three dummy batteries. Though this could damage your LEGO because of the over voltage (11.1 volts instead of 9 volts).

I don't know if the RC system would accept those batteries. I thought about getting some 1.6v Ni-Zn to use but I didn't know whether they would work.

i once read somewhere that lego uses 12v motors, so that it is hard to destroy them. i wouldn't use 11 volt though.

I think Sheepo did a PF tips and curiosities video which said that.

[MajorAlvega]

Eneloop got famous some years ago for their low internal resistant (and not for their capacity). They are NiMH but have a very low discharge rate so are quite good to charge at home and take to an exhibition.

The low internal resistance allows very high discharge rates so they perform more like LiPo batteries but can be charged with ordinary AA or AAA chargers.

There are other low resistence / high performance brands in the market today, some probably even better. But the name Eneloop is strong in the market and in people memory.

[zux]

The issue you are facing tells me your MOC uses high speed/low torque setup, which would explain why model could go downhill but nothing more. What are your wheels and gear setup?

[hadidi1999]

I know, MajorAlvega, Ever since I have meet Eneloop (before it was owned by Panasonic) I loved them. Then will probably be my 1# rechargeable batteries for a long time. Don't know why I really love them though.

[DamonMM2000]

I use 2400mAh Energizer 1.2V Power Plus Rechargeable batteries, and they last quite a while for me.

[deehtha]

Mixing different types of batteries, even same brand rechargeables with different mAH rating is not good.

If I recall right, the motors are all 12v but the control circuitry in the IR receivers gets damaged above 10. I don't know about the rc unit though.

As for not driving very well, without seeing the model, we can't help you too much.

[750ACE]

In 2012 I bought a 16 pack of 2000mah eneloop NiMH batteries and a PowerEx MH-C9000 charger / conditioner. To this day they charge full, hold charges extremely well and discharge at correct rates. I recommend these batteries. I went with that PowerEx charger because of the break in cycle and conditioner cycle.

[Moz]

Your problem is not current, it's voltage. You're right about the 1.2V being the issue - Lego motors are designed to take 9V, from 6 1.5V batteries, and the IR controllers will take 10V or so without problems. The difference between 7.2V from the NiMH and 9V from disposable batteries is significant, you get less power at the same current (and are actually fairly close to the P=VV/R law that applies to pure resistors), so the motors spin more slowly and have less torque.

The "1.4V when fully charged" isn't very useful, it will drop to 1.3V or less very quickly when you start discharging the battery.

I am starting to experiment with 14500 LiIon batteries (AA sized), because 3 of those in series is a bit over 11V when fully charged, so if I charge them to 3.5V I can safely use them in the Lego battery pack (I short one side of the pack and fill the other). That gives me about 800mAh of capacity, but the LiIon cells are happy to deliver 3A or so and that will power 2 IR controllers with XL motors on them (just not for very long). I'm tossing up using a 3S2P setup with 6 cells, but charging becomes more tricky as the paralleled cells have to be very tightly balanced when I connect them. I looked at NiZn batteries but they're really unreliable and even the good ones tend to fail quickly (to get 6 that work you really need to buy 12, and to have 6 working after 100 cycles you may need to start with more than 12). Likewise "rechargeable alkaline" batteries don't work very well in high-current situations like this. So I've stuck with LiIon 14500 cells.

The advantage is higher voltage, of course, but in a way that doesn't visibly modify the Lego. It's not 100% purist, but it's very close and IMO no worse than using disposable batteries.

[Limga]

I have some questions about batteries too. May I ask them there?:)

Li-Po have very stable voltage, that can hold the load without much decrease. Six usual AA or AAA batteries provide about 15 percent more voltage and, therefore, power. However it seems like the voltage provided by six usual batteries can decrease significantly under load. There is coming competition in Moscow and I wonder whether it is better to use Li-Po or usual battery pack with non-rechargeable batteries. Also I heard that there are some expensive types of non-rechargeable battery, that have very stable voltage during their work, does anybody used them?

[LennyRhys]

Also I heard that there are some expensive types of non-rechargeable battery, that have very stable voltage during their work, does anybody used them?

You're probably thinking of lithium batteries (as opposed to their rechargable counterpart, lithium-ion). Lithium batteries are by far the best batteries that money can buy because they keep their voltage for most of their usable life, e.g it will take a long time for a 1.5v AA to fall below 1.4v. The only reason people favour rechargable batteries is because they are cost-saving, but the trade-off there is the lower voltage of 1.2v.

[Zerobricks]

Its simple, you need voltage to have the needed current. You may have the best 1,2V rechargable battery but it will never put out the same currenton to the same load as a 1,5V one.

Edited February 25, 2016 by Zblj

[Limga]

You're probably thinking of lithium batteries (as opposed to their rechargable counterpart, lithium-ion). Lithium batteries are by far the best batteries that money can buy because they keep their voltage for most of their usable life, e.g it will take a long time for a 1.5v AA to fall below 1.4v. The only reason people favour rechargable batteries is because they are cost-saving, but the trade-off there is the lower voltage of 1.2v.

Thank you. I read about lithium batteries and looked at their discharge curves with different current consumption. It really looks like they are the best if there is no need in recharge and if you can afford them:) I will use them on competitions.

Its simple, you need voltage to have the needed current. You may have the best 1,2V rechargable battery but it will never put out the same currenton to the same load as a 1,5V one.

It isn't so simple. I'm sorry but I think that you are wrong. Power supplies, such batteries are, do have an internal resistance. When batteries have to give more current than they can give at, for example, 1.2 voltage level, the voltage is decreasing down to, for example, 1.0. Different types of non- and rechargeable batteries have different properties. For example, rechargeable NiMH battery can provide 2A current at 1.2V (for example) but some even cheap batteries with 1.5V won't even work if the load requires 2A current.

[Zerobricks]

Yes internal resistance does play a role, but remember non-modified PF components can max drain around 1 amp in continous use, so the internal resistance at such low currents shouldnt be so noticable.

[dpkong]

Funny LEGO never made a new battery box to encourage use of 1.2V rechargeable batteries. So much for being Green and all...

[dr_spock]

LEGO battery boxes have a resetable fuse that cuts out at around 750 mA if I am not mistaken.

[Technic Jim]

Thanky uo all. I have bought some eneloop batteries and have just gone and tried them out. They work fine, but after a short while the model stopped working. It was driving fine then it started jerking forwards and backwards and cutting off. If I lift it off the ground it does the same thing just less violently. I think it is because I have got a bad connection between the controller and model but the 9V battery in the controller was at 8.3 volts, more than enough voltage. So, I don't know what the problem is. I don't think the model is built badly - it is a direct drive from two rc motors on low output put through a differential at the front and back with 68.8 x 36ZR wheels.

[hadidi1999]

Oh I see, I have experienced that in RC cars. If outside then direct sun will interfere. If inside, a radio or telephone or tv. It is not a motor problem, it is the connection, check all the connections are secure, and nothing is in the path of the receiver and the remote, and change the batteries of the remote to make sure, or try a different receiver/remote combination if you have one. Also of course make sure they are on the same channel, you know "A" or "B"

Also, make sure the remote and receiver are compatible, which they probably are, and that nothing is broken. You have to go through everything possible.