Galaxy mp5k 7.4 vs 8.4 battery

[Halo]

I’ve a second 7.4v battery in its packet still but I’ve seen people using 8.4v, should I be taking it back to swap for an 8.4?

[EDcase]

A 7.4v LiPo battery delivers the equivalent power to an 8.4v NiCd but in a smaller package.

Does it show the specs?

 

 

 

Edited December 19, 2021 by EDcase

[Halo]

5 hours ago, EDcase said:

A 7.4v LiPo battery delivers the equivalent power to an 8.4v NiCd but in a smaller package.

Does it show the specs?

 

 

 

it’s a nuprol 1200mah 7.4v 20c skim deans

[EDcase]

Its not a great battery but good enough for at least half a game day (maybe a whole one) with medium amount of shooting  (not auto all the time).

 

 

 

Edited December 19, 2021 by EDcase

[Halo]

Is there a performance benefit in a 8.4 version?  I’ve a mosfet inside also so the stock battery had to be removed to allow a slimmer one in there

[Rogerborg]

8 hours ago, Halo said:

Is there a performance benefit in a 8.4 version?

 

vvv

 

On 19/12/2021 at 02:03, EDcase said:

A 7.4v LiPo battery delivers the equivalent power to an 8.4v NiCd but in a smaller package.

 

That.  And different chemistries means you can't really compare like for like.  Notionally an 8.4V NiMH should spin a no-load motor a little faster than a 7.4V LiPo, but those aren't the voltages that you'll actually see.  Most chargers will take a lipo up to a reliable 3.7V per cell i.e.  8.4V for a 2-cell rather than 7.4V.  A NiMH "8.4V" pack is 7 x 1.2V cells in series but chargers don't know that.  All they can do is to stuff charge in until the battery resistance spikes / the charging current drops, which might be at any point depending on the worst cell in the pack.

 

So much for voltage.  The lithium cell will also be able to deliver more power, and will deliver it more consistently as it discharges, which will let your motor pull the spring as fast as it's able to.

 

They both work, I'm not saying that you must get lithium based cells, but I prefer them.

[BigStew]

On 19/12/2021 at 01:11, Halo said:

I’ve a second 7.4v battery in its packet still but I’ve seen people using 8.4v, should I be taking it back to swap for an 8.4?

I would put money on the reason people are using an 8.4v nicad is that it came with the gun or they pulled it out of storage after 15 years.  

Edited December 21, 2021 by BigStew

[Cannonfodder]

I use a 7.4v LiPo as its an easier fit 

[Halo]

Even with the 7.4 slim in there it’s abit of a pain in the ass and the butt plate seems to need jamming in against the wiring which can’t be a good thing!

 

is there kind of any 1-2cm extension plates perhaps to allow a little room without going full stock etc?  It’s the PDW version

[Rogerborg]

I went for practicality over posability and binned off the charging handle.  No more HK slap, but a fair bit more room in the tube.

 

Also, I rear wired mine, as I couldn't be doing with all that fiddling around at the front.  There's room to run wires behind the gearbox up to the tube.  Deans connector, of course.

 

With all of that done, I can actually get a 116mm x 17mm x 13mm 7.4V lipo in there with a small mosfet as well.