Battery Strength Indicator

There is a very small amount of current consumed anytime the batteries are in the controller, but it's in the microamp range.  Usually, the issue with batteries is self-discharge, have you looked into the batteries that specifically advertise low self-discharge?  FWIW, I find that Lithium primary cells last a very long time in the CAB2, far longer than the rechargeable batteries.

As a test, see how long some standard AA alkaline batteries last in the unit.

If you don't intend to use the base for charging place a small piece of paper in the cradle over the contact points.

Both the remote and the base contacts are covered with electrical tape and the charging circuit is turned off.

I've found that batteries in my Legacy Cab2 last way longer than batteries in my DCS Controler. Just throwing this out there. 

The rechargeable batteries I use in the Legacy controller seem to run down much quicker than the Alkaline batteries I use in the DCS remote, so my experience is opposite of yours.  I'm still using the batteries that Lionel sent when I shipped both remotes back to them, though I also have some other rechargeables I'm going to test.

Batteries in the old cab 1 remotes seemed to last forever, legacy, maybe a couple weeks depending on your operating time. I turned off the backlight and batteries seem to last noticably longer.

The irony is the old cab 1 took four batteries. The cab 2 only has room for three and all of the added electronic wizz-bang stuff drawing more power.

You're right Rick.  Though I don't use it much nowadays, the old CAB1 has had the same batteries for close to a year, and it gets used on the test bench a few times a week.  After a few hours, my Legacy CAB2 is looking for a recharge.  The DCS Remote lasted quite a while on the 4 AAA Alkaline cells, I just finally saw the BAT indicator, pretty impressive battery life for that one.

Read my post. There is electrical tape over the contacts.