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Antigravity U1R lithium battery for NA/NB

Antigravity U1R lithium battery for NA/NB

Regular price $619.99 USD
Regular price Sale price $619.99 USD
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Fits: 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1999, 2000, 2001, 2002, 2003, 2004, 2004 MSM, 2005, 2005 MSM

Emissions: Emissions do not apply.

Shipping restrictions: Continental US only

Warranty: 5 years

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Please note that these are only drop-ins for NAs and NBs. These will technically fit NCs and NDs, but it's a physically smaller battery. The right size is a 51R, which we don't currently carry. 

Batteries have always been the densest thing in your car, and the easiest way to lose weight. However, there have always been compromises you have to make. While our new lithium batteries aren't without compromise, the compromises will be a non-issue for most, and they come with a host of advantages beyond their light weight. 

But wait! Lithium batteries haven't been used in street cars, right? Not really - Porsche, BMW, Mercedes-Benz, and McLaren have all been using lithium (specifically LiFePO4) batteries in production cars for nearly 10 years. 

Why do you want a high quality lithium battery, specifically the Antigravity battery? Here's a quick list: 

  • Save almost 17 lbs over the stock battery (stock is 24 lbs, this one is 7.4 lbs)
  • 8-10 yr lifespan (and a 5 yr warranty) - the initial purchase price is higher than a "standard" battery, but the overall cost is lower, thanks to its long lifespan
  • Intelligent BMS (battery monitoring system) - the onboard system won't allow over-discharge, over-charge, over-voltage, or short-circuit
  • Works great with your existing electrical system, no need to change anything else
  • Higher resting voltage = better starting (not so high to damage your car)
  • More cranking Amps than your stock battery. Specifically, 925 CA, while your stock battery is probably around 400 CA.
  • These are "LiFePO4" (lithium iron phosphate) batteries, which are much safer than lithium polymer or lithium cobalt. These aren't the kind that catch on fire (you're probably carrying one of those in your pocket).
  • Re-Start technology, which ensures that the battery always has enough reserve to start the car, even if you leave the lights on - if you end up with a dead battery, push the button on top of the battery or on the included remote, and the battery will reconnect itself (internally) so the car can be started
  • These will never sulfate like a lead acid battery. Please be aware that this means you must use a LiFePO4-specific charger (like the one we sell), a generic charger will damage the battery. If you don't have a charger for your current battery, you shouldn't need one for this battery.

Why wouldn't you want this setup? Fair question, but there's really only one drawback - performance in cold weather. If your car is frequently stored in freezing conditions (a warm garage when it's cold outside doesn't count) or frequently driven and parked in <20°F / -7°C conditions, this isn't the battery for you.

We've found that the fact that there's a lower temp limit often prompts a "what about a high temp limit" question. Pragmatically, if you're not having issues now you probably won't with this battery. If it's a "normal" underhood install, you should be fine, but if it's right next to the exhaust, with no heat shielding - which is a bad idea in general - you could have issues. Specifically, as long as the battery's temp stays under 190°F (88°C), it'll be fine.

As far as capacity, when comparing to "normal" batteries, bear in mind that lead-acid batteries can't be discharged as far as lithiums, so a 20Ah lithium battery (like this one) is roughly equivalent to a 40Ah lead-acid battery. Your stock (or stock replacement) battery is probably around 25 Ah, so you - effectively - have more capacity with this battery than your stock battery. 

Due to shipping rules, these can only be shipped to the lower 48. If you're having issues adding this to your cart, please check your shipping address.

Customer Reviews

Based on 1 review
Buddy H.
Flyin Starter for the Win

Wow. The grin couldn’t come off my face the first time the key was turned. It’s like I added a turbo kit to the starter. Unless I’m caught in an emergency, I will use these in all our Miata’s (family has four now). No more lazy starts, slow cold starts, or dead batteries for us. I bought it for a slow starting 95 with an aftermarket ecu. I never could have imagined the difference.