How can i get up to more than 10 battles without relying on the random pre-battle chances?

Short Answer: Yes, but with the random Brave Attack bonus or the right setup

I will reference abilities from the list on this website (multiple pages): http://www.gamefaqs.com/3ds/740205-bravely-second-end-layer/faqs/71509?page=4#Job Classes and Abilities/

I may have found a better setup that can get you up to 99 battles, without relying on chance (like you were wanting). I'm referencing this post, http://www.gamefaqs.com/boards/740205-bravely-second-end-layer/73375249.

You need to have Ranger and Red Mage unlocked, with the Red Mage's ability BP Recover. You want to make sure all 4 characters can kill monsters in 1 hit with physical attacks, use the ranger job as the primary or secondary job, and equip the Red Mage's BP Recover abilities.

The strategy is simple, use Berserk on all 4 characters (setup on auto preferred), which will increase BP by 1 and force the character to attack. As long as they don't take more than 1 turn to kill everything, this will easily get you up to 99.

[[Original 10 battle Strategy]]

I will reference items from the list on this website: http://finalfantasy.neoseeker.com/wiki/Items_(Bravely_Second)

So this would require the Torso Armor, Brave Suit, as this will give just enough BP to reach 10+.

Optional items that improve the random Brave Attack Chance:

• Venture Badge: Increase Brave Attack chance by 10%
• Whisker Sense ability (Catmancer): Increase First Strike and Brave Attack chance by 5%

The information below assumes we get into a battle with +1 BP for everyone (Brave Attack/Characters feel brave). Every character has to be able to kill every monster in 1 turn.

If you add up the BP as turns, you will get 9 turns + extra to finish up the mobs on the tenth round of monsters. I will break it up to make it easier to read (hopefully).

Starting BP, character 1: 2BP, 2: 1BP, 3: 1BP, 4: 1BP

Note: 1 round = wiping out an entire group of monsters in 1 turn.

• Character1 kills the first 3 rounds on the first turn and ends with -1BP (+3 rounds)

• Character2 kills the next 2 rounds on the first turn and ends with -1BP (+2 rounds)

• Character3 kills the next 2 rounds on the first turn and ends with -1BP (+2 rounds)

• Character4 kills the next 2 rounds on the first turn and ends with -1BP (+2 rounds)

• All characters take 2 turns to finish mobs (+1 round)

3 + 2 + 2 + 2 + 1 = 10 (for the lazy or math-challenged).

This will give you 10 rounds of bonuses minimum based off of the information I provided, but please let me know if anything wasn't clear.

Disclaimer: This isn't the only strategy to get 10+ rounds, but it is simple and can be done as soon as you acquire the Brave Suit.

Instead of relying on brave attacks and random chance, run the BP Recovery ability from the Red Mage Job (requires Job Level 5). This ability give your character 1 BP when they are inflicted with any status condition.

There are many ways to use it, but the easiest involves having both the Ranger and Red Mage Job. It essentially boils down to having the aforementioned Red Mage ability equipped and use the Ranger's Berserk skill to inflict the Berserk on your character. You can repeat this a long as you like. However not that you will only be able to use normal attacks, so it's recommended that you find ways to boost the number of attacks and hits your characters do physically. Abilities like the Fencer's Eye of the Wolf (starts the first battle (in the chain) in Wolf Stance (+25% P.Atk/+25% M.Atk on top of your max cap)) can help give you a boost.

An easy way to rack chains to do this and rack up chains is Geyser Grotto in the Eisen Region. The second area in that dungeon will automatically inflict the Berserk status on your characters. Equipping abilities like Triple Wield and P. Attack 20% up from the Charioteer job can ensure you get more hits off and do more physical damage to enemy mobs. Not that there are risk involved with this method, since you're berserked, you can't res any KOed character or use Bravely Second, so it might help to equip Agility boosting items to ensure that your characters hit first.

If you're just looking to increase the number of battles you can go beyond five, I'd recommended equipping the abilities Whisker Sense and Precognition from Catmancer and Astrologian (no more than one copy of each ability); the Venture Badge and Gale Hairpin accessory (again, no more than one of each, if you somehow acquired multiples); and Staff, Dagger, and Fist weapons. This will halt enemy First Strike and Brave Attacks while improving the chances for your own, and will give you good BP/HP/MP recovery from the weapon's Recovery Specials.

You won't go as many battles as the Red Mage/Berserk build, above, but it's safe and flexible enough that you can use it for most of the game. I've gotten the Max Bonus many times using this strategy, plus whatever jobs, abilities, and equipment makes sense for the current area.