Moonshadow
Junior Member
My V3i didn't come with the rechargeable battery pack but I had no desire to do so because it has a finite lifespan. It came with two AA battery holders and I was satisfied with the performance of these, but I got tired of changing the batteries. Good rechargeable batteries or name brand AA batteries would last about 1.5 hunts, but I noticed that the AA batteries just wouldn't hold a voltage above 10v for too long. 10v+ seemed pretty stable, but I noticed subtle performance anomalies when it got below that. I know that the V3i has a voltage regulator and I think it steps it down to ~8v, but I found it almost unusable at ~9v. My theory - even thought the batteries hold that potential, they just don't have the strength to hold a steady voltage when it gets that low.
Anyways, I work on medical equipment at a variety of hospitals and one day it just clicked. All I need is a 12v battery and I'm set. We change batteries out at regular intervals and most of the time these batteries are still perfectly functional. Some batteries are extremely high quality lithium batteries that cost $400+!!!
So, I found the perfect battery- a Li-SO2 7.5Ah battery that is very light weight for the size and capacity. During regular use, it holds steady at /}\
11.19v. When I turn TX boost on, it holds steady at 10.98v. Lithium batteries hold at the voltage until the very end - they just drop off.
I soldered a wire to the terminals on one of my spare battery packs, drilled a hole to run the wire through so that it fit in the V3i with ease. The wires get soldered to the terminals on the decommissioned batteries as I go through them. The battery pack is taped to the bottom of the detector via crude but effective electrical tape. It makes it easy for me to undo this mod very quickly if I need to. I don't notice any weight difference between this and the AA battery pack.
It may be crude, but it makes the V3i extremely solid and reliable. I don't usually worry about running out of juice, but I do keep a loaded AA battery pack in the car as a backup. I've been running my V3i like this for weeks and haven't had a battery fail yet. I had another AED battery that I used for a week, but I pulled it when it got to 10.8v just because it was a lot older.
I know this isn't a solution for everyone, but it makes me very happy and I thought I'd share!
Anyways, I work on medical equipment at a variety of hospitals and one day it just clicked. All I need is a 12v battery and I'm set. We change batteries out at regular intervals and most of the time these batteries are still perfectly functional. Some batteries are extremely high quality lithium batteries that cost $400+!!!
So, I found the perfect battery- a Li-SO2 7.5Ah battery that is very light weight for the size and capacity. During regular use, it holds steady at /}\
11.19v. When I turn TX boost on, it holds steady at 10.98v. Lithium batteries hold at the voltage until the very end - they just drop off.
I soldered a wire to the terminals on one of my spare battery packs, drilled a hole to run the wire through so that it fit in the V3i with ease. The wires get soldered to the terminals on the decommissioned batteries as I go through them. The battery pack is taped to the bottom of the detector via crude but effective electrical tape. It makes it easy for me to undo this mod very quickly if I need to. I don't notice any weight difference between this and the AA battery pack.
It may be crude, but it makes the V3i extremely solid and reliable. I don't usually worry about running out of juice, but I do keep a loaded AA battery pack in the car as a backup. I've been running my V3i like this for weeks and haven't had a battery fail yet. I had another AED battery that I used for a week, but I pulled it when it got to 10.8v just because it was a lot older.
I know this isn't a solution for everyone, but it makes me very happy and I thought I'd share!
