The Sanyo-Panasonic NCR18650BF offers an affordable 3400mAh battery with a decent continuous yield of 6.8A

Specifications
Nominal Capacity: 3400 mAh
Nominal Voltage: 3.6-3.7V
Max. Continuous Discharging Current: 6.8A

Regarding Exchanges/Warranty

Due to the nature of this consumable product, no returns/exchanges with this product or other replacements are allowed unless the product is DOA

Warranty coverage will be 6 Months Full Warranty (against explosions/leakage/venting) unless battery has been found to be pushed beyond its stated specs, misused or overdischarged 

Warning

• CAUTION: when working with Li-ion cells, they are very sensitive to charging characteristics and may explode if mis-handled
• User should have enough knowledge on Li-Ion rechargeable batteries in charging, discharging,and assembly before use
• Put the batteries in fire-proof container when bringing them out or when they are not in use
• Do not put batteries on wood surface, carpets or flammable materials when charging
• Never leave battery un-attended when charging (especially overnight)
• We are not responsible for any damage(s) to property or injuries if there is any modification of the batteries in form, shape, or when made into packs
• We are not reponsible for any damage(s) to property or injuries arising from possible explosions, leaks or fires resulting from the use or misuse/mishandling of these Li-Ion batteries