Danbury clock 'things remembered'. How do I access the battery?

I am unsure wha you mean by "fix the pendulum". If you mean it stopped swinging, there are two reasons: first check the battery and contacts. Remember, even a new battery can be bad, which is why new things come with warranties. The other thing is quartz movements usually don't last too long. If the pendulum is not swinging, and is correctly attached to the movement and the battery is good, then the movement has gone bad and you need a new one. Most all clock shops keep quartz movements on hand. If you are a do-it-yourself type, you can get them off the Internet. Be sure to remove the old one first and check how thick the dial is, that's how they sell them by dial thickness.

Bradford is a high end retailer. You can contact them because if the item is not over a year old then it is warrantied. The other thing is you can email them to see about the clock works inside the unit. See this page and look for "contact us" at the bottom.

http://www.howardmillerusa.com/customer-support/how-to-setup-howard-miller-grandfather-floor-clock.html
Click on this link for the setup info you need and read

The things remembered clock is just tension fit in the housing. Easiest way to get it out is to get a plastic suction cup. Press the suction cup onto the face of the clock and pull and jiggle till the clock comes out. This way you wont gouge up the wood trying to pry the clock out with a screwdriver. It takes an N cell battery: https://en.wikipedia.org/wiki/N_battery

The clock is just tension fit in the housing. Easiest way to get it out is to get a plastic suction cup. Press the suction cup onto the face of the clock and pull and jiggle till the clock comes out. This way you wont gouge up the wood trying to pry the clock out with a screwdriver. It takes an N cell battery: https://en.wikipedia.org/wiki/N_battery

The clock is just tension fit in the housing. Easiest way to get it out is to get a plastic suction cup. Press the suction cup onto the face of the clock and pull and jiggle till the clock comes free. This way you wont gouge up the wood trying to pry the clock out with a screwdriver. It takes an N cell battery: https://en.wikipedia.org/wiki/N_battery

If it is this pocket watch, then the crown (the bit you turn to wind the watch) has 3 positions. Position 1 is when the crown is pushed in all the way. Position 3 is when the crown is pulled out as far as it will go. In between position 1 and position 3 is a place where the crown will stop, this is position 2.
To set the day of the week, pull the crown out to position 3 to set the time. When you set the time, the bottom dial with also turn to set the hour on the 24 hour clock, if you turn the crown enough to cycle through a whole day the day of the week dial will also turn. Keep turning the crown until the time is set on the proper day of the week.
To set the date, pull the crown out to position 2, and turn it clockwise until the hand on the date dial points to the correct date.
Hope this helps!

The whole front square face of the clock has 4 little nails which are located in the middle of each side (inside and next to the edge of the joint), so you have to carefully insert a screwdriver and lever the front out. After this you have to remove the hands (remember to set the clock and alarm hand to 12:00 before taking those away). The face will be loose, and you'll have access to the mechanism. Clean the alarm contact (look for a double silver metal arm that touches an small bronze stick. Alarm button can be release by gently lever the little nail that shows in the center when button is up at clock's backside.
Cheers from Argentina

These are general quartz wall clock instructions as I dont know enough about what type/style of clock you have.

Open the access door to the dial and hands of the clock if required. Some battery-operated clock movements are sealed inside the clock case with a back panel that is screwed in place. To gain access to the hand set knob, remove the back panel screws using the appropriate tipped screwdriver.

Turn the minute hand (or turn the hand set knob at the rear of the movement if access is available) carefully counterclockwise or clockwise until the correct time is reached. Keep in mind that using the hand set from the rear would require turning the knob in a clockwise direction in order for the hands to turn counterclockwise.

Move the hour hand carefully with your fingers near the center of the hand to the hour that the clock is striking if the striking chime is not counting the correct hour. The hour hand is a friction fit hand and will move without engaging the minute hand.

Replace the back panel and tighten the screws with the screwdriver if removal of the back panel was necessary to access the hand set knob.

Close the front access door if required.