Have you seen this design?
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Yes, you can run your iPod speakers on rechargeable batteries conveniently. Try to search for the best lithium Ion rechargeable battery manufacturer. Rechargeables are not only more money than single-use rechargeable batteries plus charge, but the price of a quality charger may negate their value altogether depending on use. Another potential problem with rechargeable batteries is that they can often become weak and unpredictable with age.