Cheap trickle charge from wall wart?
With no more information than you have given I would have to say that trying to recharge your battery in this way is a bad idea. Recharging batteries is a tricky thing to do properly, and you need to know exactly what kind of battery you are charging.

The arrangement you propose would not supply more than about 8.3V to the battery, even at extremely small currents. A trickle charge of 1mA reduces the charging voltage to under 8V. Is that enough to charge it? No one can say.

How much current does your load require? Let's say the load needs 10mA. If the wall wart is providing that current then the drop across the resistor is 6V and the drop across the two resistors is about 1.4V. The voltage available at the load falls to less than 2V and the voltage at the battery falls under 3V. The wall wart isn't doing you any good at all in this scenario.