L298 H Bridge.

My circuit consists of an L298 H bridge that has been paralleled to deliver more current.

However, when the bridges are operated in one direction they deliver more current than when operated in the other...

Why could this be? How can I correct this?

what kind of control do you have?
at a guess I would say (if you have a current-controller) is that you have an offset in yr demand,feedback or gain-blocks (or PWM generation is slightly biased)

too little info (ie lack of cct) to pin it down, but my money on offset

I am trying to charge a battery using charge and burp method... The H bridge current reveral is used to burp (discharge for a short peiod of time). There is also a PWM involved.

I am using a current source...

The difference of current in the directions is as much as between 1.0A and 2.1A

Well without cct the problem cannot be found, but I stand by an offset somewhere in yr cct