Icom T7H (HAM radio)- Li Ion vs NiMh?

[GarageBoy]

Okay, on this radio, the input voltage is anything from 4.8V-13V. My buddy currently uses the stock NiCd (9.6V 650mAh) in it and would like to upgrade. My options are currently 6AAs for 7.2V, but @ 2500mAh or 3x14500s, which would give me 12.6V @ w/e the current Li Ions are.

Which would be the better choice? I'm not sure if output power is dependent on voltage or current.

 

[Skibane]

If he's planning on being able to use the radio during an emergency or extended power outage (and what ham doesn't make SHTF plans?), any battery holder that accepts AA cells is probably a more versatile choice. Unlike proprietary LiIon packs, NiMH AA cells are inexpensive and usable in so many different devices - which greatly increases the chances of having plenty of spares on hand.

Also, standardizing on the AA format means that the radio can also be powered on alkaline cells in a pinch.

The only down side is that power output is usually dependent on battery voltage. So, he'll probably have less transmit power on 6 AA cells, but longer run-time (due to both the lower transmit current drain and the higher capacity of the NiMH cells). In practise, this isn't much of concern - There aren't many circumstances where 5 watts of transmit power will provide any significant improvement over 3 watts, for example.

 

[GarageBoy]

Well we have 4xAA holders for it, I was just gonna pop the 14500s in there with a dummy

 

[SilverFox]

Hello GarageBoy,

In general, NiMh cells are more robust than Li-Ion cells with regard to rough handling, overcharging, and over discharging. Li-Ion cells don't self discharge at a rate that is worth worrying about and they weigh less, if that is a consideration. I would lean toward NiMh, and consider the low self discharge cells, such as the Eneloop cells.

Now, if you can figure a way to put 18650 cells in, my opinion may change. Better yet, go with the 26650 A 123 cells.

Tom

 

[Litec]

Hello GarageBoy,
I think Skibane has the best suggestion. Go for a dry cell case. I have several handies, Icom(including T90) as well as kenwood. Whenever I buy a new handie, I make it a point to get a dry cell case. You may have lesser RF output, but you can make it up by using a 'gain' duckie. Diamond duckies far outperform the stock duckies that we get with most radios.
Regards
VJ

 

[Litec]

Hello,
Another point worth noting is...difficulty in opening the sealed case. It is very cumbersome I think. Secondly, your wall charger is going to take eternity to charge your new 2700 mah Nimh thru the rig.
VJ

 

[GarageBoy]

I also forgot to mention, the 6AA batt case is twice the size of the 4AA one. Thanks

 

[Litec]

Hello,
With the 4AA case you may get a Watt or half less than 6AA, but your rig will surely look and feel lighter.