(7 Reviews)

12V 40AH Lithium Battery

1240-BT

12V40AH Sport Series Lithium Battery with Bluetooth and Built in low-temp charging protection! (1240-BT).


Customer Reviews

Jason
Rating: 5/5
Great Turnaround, Professional Communication
The world if batteries is complicated and full of sub par products. Millertech has built a company that rejects the quick, detached, Chinese-built approach and opted for a premium, personable and professionally assembled product that shines above the rest. NOT ALL BATTERIES ARE EQUAL, and USA quality is always worth the price. Weather im on the water or heating my ice fishing tent I need a battery that is first and foremost reliable. Millertech delivers that with unmatched quality and service.
Tue Feb 17 2026 18:16:17 GMT+0000 (Coordinated Universal Time)
Ron gray
Rating: 5/5
Service oriented company beyond compare.
Bought 2 100 amp for bow Minn Kota, one 100 amp for 115 hp Mercury one year ago. Did a lot of research with different lithium battery manufactures and none of them compared to Miller Techs knowledge, expertise and willingness to assist me. Wonderful product and getting ready to order a 40 amp for my forwarding face sonar with their battery charger.
Sat Jan 24 2026 19:02:17 GMT+0000 (Coordinated Universal Time)
Joe Becker
Rating: 5/5
Quality product!
12V 40AH Sport Series Lithium Battery w/ Bluetooth (1240-BT)
Wed Nov 05 2025 13:33:26 GMT+0000 (Coordinated Universal Time)
Christopher Sanno
Rating: 5/5
Great Product
The 40 Amp Hour is Perfect for my Garman 106SV with Live scope bundle. I’m able to fish 14 hours a day without worries.
Tue Aug 19 2025 23:21:40 GMT+0000 (Coordinated Universal Time)
Cheryl Bevan
Rating: 5/5
12V 40AH Sport Series Lithium Battery w/ Bluetooth (1240-BT)
Wed Jun 18 2025 00:31:32 GMT+0000 (Coordinated Universal Time)
Tripp Poplin
Rating: 5/5
Best batteries available
Tue Apr 01 2025 14:47:46 GMT+0000 (Coordinated Universal Time)
Larry Treece
Rating: 5/5
Battery
Shipping was fast. Haven’t hooked up the battery yet but I’m sure it will work fine.
Thu Dec 05 2024 15:10:00 GMT+0000 (Coordinated Universal Time)

What the pros are saying about MillerTech batteries