Does the LiPo PF battery box have a lower current limit than AA batter

[Zerobricks]

I've been playing around in ym AMG 6x6 and I swapped the V1 receiver with the V2 using the LiPo battery box. There was no obvious difference in performance... But when I swapped the abttery box with the AA one, there was some real power up.

I know the voltage is slighty higher, but that means the current is also higher and the protection IF the same as in LiPo should activate faster but it did not...

So can anyone check, confirm or explain this behaviour to me? Also what are your experiences with AAA battery box?

[re465intube]

Hi!

Electric power P is Voltage * Current: P = UI.

So, with same current, but higher voltage, you get more power.

LiPo has 7,4 volts and AAA has over 9 volts

That is the disadvantage of LiPo.

The V2 is better, dropping less voltage .

Watch this guys video: Lego Battery Box Mod

br. re465

Edited August 14, 2014 by re465intube

[Zerobricks]

I know that but the problem is higher voltage makes a higher current which means if the protection limiter is same in both boxes, that the AA should shutdown sooner!

[re465intube]

You havent opened both battery boxes?

I think, that Lipo has much more of electronics inside, to prevent overheat or blowup.

I have opened and bypassed that protector in my 8881 AA B-box. It didnt have any markings.

Before it could not handle 2 XL, now no problem and its not really overheating.

Another thing is those lego wires, they are quite thin material. From B-box to XL voltage drops 2 volts

meaning XL runs on 7 volts only. So theyare kind of overload protectors themselves.

[Zerobricks]

2 volts voltage drop? You must have some really bad wire than Yeah could be the LiPo is better protected due to the nature of the power source...

[re465intube]

Not bad wires, the regular lego-wires. I have voltage-meters, powersources etc to check this

I have a waterpump with XL-motor and it wasnt pumping so well at first. Then i measured wires and XL taking max power caused this drop

I put my powersource on XL and 9.0 volts/ 0.95 Amps make it rock.

But to your original question:

Resettable PTC fuse:

AA B-box: HL5L

Lipo box: S85L

not the same i think.

Dont know what source lego uses but here is an sample:

http://www.littelfuse.com/products/resettable-ptcs/surface-mount/0805l.aspx

0805L <- hmmmm....