Group 8D Batteries - Dimensions, Features and Recommendations

group 8d battery mBCI Group 8D batteries are large and heavy commercial batteries, often used for off-the-grid applications, as solar batteries, as RV house batteries, for security, medical and standby applications, for powering various industrial vehicles and applications etc.

BCI Group 8D lead-acid batteries are commonly Absorbent Glass Mat (AGM) or Gel-Cell Sealed Lead Acid (SLA) batteries, with lithium iron phosphate (LiFePO4) 8D batteries being relatively rare.

Group 8D Batteries Dimensions

Group 8D batteries are large batteries with their maximum dimensions (L x W x H) of 20 3/4 x 11 1/8 x 9 7/8 inches (527 x 283 x 250 mm). We emphasize this 'maximum dimensions' since some of the BCI group 8D batteries are closer to group 6D or group 4D, but they still belong to the 8D battery group.

Hence, these batteries vary in weight (~130 - 190 pounds), 20h capacity (200-350 Ah), Reserve Capacity (RC; 450-780 minutes), CCA values (~1350 - 2250 Amps), MCA values (~1700 - 2700 Amps), number of charging/discharging cycles, etc. But they also differ in the price, too.

Note: some deep cycle 8D batteries, although large and powerful, are intended only for (relatively) low current discharge applications and don't even mention their CA/MCA values - don't use them as cranking batteries, except for relatively small engines.

The following chart lists the most popular group 8D batteries on the market:

Model Battery Type Chemistry Ah CCA MCA RC Weight (lbs/kg) Dimensions
(LxWxH, inches)
Fullriver DC260-12 Deep Cycle AGM 260 1525 1830 578 170.6 lbs; 77 kg 20.51 x 10.59 x 8.82 -
GreenLiFE GL260 Deep Cycle LiFePO4 260 - - 624 80 lbs; 36.24 kg 20.44 x 10.57 x 8.70  
Lifeline GPL-8DL Deep Cycle AGM 255 1350 1675 550 156 lbs; 70.8 kg 20.76 x 10.89 x 9.65 -
Mighty Max ML8D Deep Cycle AGM 250 - - 600 (@24.5 Amps) 159 lbs; 72.0 kg 20.47 x 10.55 x 8.66 -
NorthStar NSB-AGM8D Dual Purpose AGM 220 1450 1800 500 152 lbs; 68.9 kg 20.36 x 10.84 x 9.61 -
NorthStar SMS-AGM8DK Dual Purpose AGM 228 2250 2700 500 187 lbs; 84.7 kg 20.50 x 11.00 x 9.41 -
Odyssey 8D-1500 Deep Cycle AGM 220 1500 1787 475 143 lbs; 64.8 kg 20.39 x 10.87 x 8.86 -
Renogy RNG-BATT-AGM12-200 Deep Cycle AGM 200 (@10h) - - 600 (@20 Amps) 129 lbs; 58.5 kg 20.50 x 9.40 x 9.40 -
Renogy RNG-BATT-GEL12-200 Deep Cycle Gel 200 (@10h) - - 600 (@20 Amps) 128 lbs; 58.0 kg 20.60 x 9.50 x 8.70 -
Sun Xtender PVX-2580L Deep Cycle AGM 258 - - 480 (@29.5 Amps) 159 lbs; 72.1 kg 20.76 x 10.22 x 9.77 -
Trojan 8D-AGM Dual-Purpose AGM 230 1450 1850 460 161 lbs; 73 kg 20.47 x 10.64 x 9.08 -
Trojan 8D-Gel Deep-Cycle Gel 225 - - 500 168 lbs; 76 kg 20.69 x 10.95 x 10.82 -
UPG 45964 UB8D Deep Cycle AGM 250 - - 600 (@23.2 Amps) 154 lbs; 70 kg 20.47 x 10.55 x 9.65 -
UPG 40702 UB8D Deep Cycle Gel 250 - - 600 (@23.3 Amps) 154 lbs; 70 kg 20.47 x 10.55 x 9.65 -
VMAXTANKS XTR8D-350 Deep Cycle AGM 350 1700 2100 780 185 lbs; 83.8 kg 20.8 x 11.1 x 9.8 -
West Marine WM8A8D Dual Purpose AGM 245 1450 1800 480 161 lbs; 73 kg 20.75 x 11 x 10 -

Note: Amazon affiliate links in the table open in the new windows, feel free to check them for most up-to-date offers and prices.

As one can see, group 8D batteries are large, strong and heavy batteries that can store and deliver large amounts of energy easily that can make damage and hurt people and animals.

Most of these batteries come with carrying handles which sounds rather convenient, but IMHO, most of these batteries should be carried by at least two adults that are used to physical labor - seriously, people get injured when trying 'just to move it little bit' or something similar.

renogy 8d gellMost 8D batteries are AGM SLA batteries, with few Gel-Cell SLA models. Lithium ion batteries (Lithium Iron Phosphate - LiFePO4) are not as common as one may hope for, but they are slowly gaining in popularity in this BCI group, too.

Group 8D batteries are commonly labeled as 'Deep Cycle' or as 'Dual Purpose', while starting group 8D batteries are so common (if present at all, due to the advances in Gel-Cell/AGM batteries). Some manufacturers label their models as 'deep cycle' and state their CCA/MCA values, which are in some cases even better than CCA/MCA values of some 'dual purpose' models.

But, like with everything in life, performances come at certain price. Here is the price comparison of the most popular models that may be found on Amazon:

Compare the prices:

Price differ significantly, but so does the warranties, number of cycles, and relative capacities, CCA/MCA and other values:

Model Chemistry Ah/Pound CCA Amps/Pound MCA Amps/Pound RC Min/Pound Warranty Number of Cycles Weight (lbs/kg)
Fullriver DC260-12 AGM 1.524 8.939 10.727 3.388 1 Year - 170.6 lbs; 77 kg
GreenLiFE GL260 LiFePO4 3.25 - - 7.800 5 Year 3000-5000 80 lbs; 36.24 kg
Lifeline GPL-8DL AGM 1.634 8.654 10.737 3.526 5 Year - 156 lbs; 70.8 kg
Mighty Max ML8D AGM 1.572 - - 3.773 (@24.5 Amps) 1 Year ~700, 50% DoD 159 lbs; 72.0 kg
NorthStar NSB-AGM8D AGM 1.447 9.539 11.842 3.289 3 Year 900, 50% DoD 152 lbs; 68.9 kg
NorthStar SMS-AGM8DK AGM 1.219 12.032 14.438 2.674 3 Year 900, 50% DoD 187 lbs; 84.7 kg
Odyssey 8D-1500 AGM 1.538 10.489 12.496 3.311 2/3 Year
(app dependant)
~750, 50% DoD
(down to 80% capacity)
143 lbs; 64.8 kg
Renogy RNG-BATT-AGM12-200 AGM 1.550 (@10h) - - 4.651 (@20 Amps) 2 Year ~450, 50% DoD
(down to 80% capacity)
129 lbs; 58.5 kg
Renogy RNG-BATT-GEL12-200 Gel 1.562 (@10h) - - 4.687 (@20 Amps) 3 Year 1200, 50% DoD
(capacity loss?)
128 lbs; 58.0 kg
Sun Xtender PVX-2580L AGM 1.622 - - 3.019 (@29.5 Amps) - - 159 lbs; 72.1 kg
Trojan 8D-AGM AGM 1.428 9.006 11.491 2.857 1 Year - 161 lbs; 73 kg
Trojan 8D-Gel Gel 1.339 - - 2.976 1 Year - 168 lbs; 76 kg
UPG 45964 UB8D AGM 1.623 - - 3.896 (@23.2 Amps) 1 Year 450-500, 50% DoD
(down to 80% capacity)
154 lbs; 70 kg
UPG 40702 UB8D Gel 1.623 - - 3.896 (@23.3 Amps) 1 Year 450-500, 50% DoD
(down to 80% capacity) 
154 lbs; 70 kg
VMAXTANKS XTR8D-350 AGM 1.892 9.189 11.351 4.216 1 Year 800, 50% DoD
(down to 80% capacity)
185 lbs; 83.8 kg
West Marine WM8A8D AGM 1.522 9.006 11.180 2.981 18 Months 300 cycles
(DoD? capacity loss?)
161 lbs; 73 kg

Note: Amazon affiliate links in the table open in the new windows, feel free to check them for most up-to-date offers and prices. Also, not all manufacturers offer the same warranty terms and conditions, so be sure to read them, especially the 'small letters'.

Note: we have really tried to verify every single bit of information in these charts/tables (like with everything on our site), but keep in mind that sometimes even manufacturers state different values of certain features for the same battery model on their own official websites...

Group 8D Batteries Features

Nominal capacity of the Group 8D batteries vary between 220 and 350 Ah and their relative capacity vary between 1.2 and 1.9 Ah per pound of battery weight. Lithium ion GreenLife GL260 feature relative capacity of 3.25 Ah/pound and may lead to significant save in weight.

Cold Cranking Amps (CCA) vary between 1350 and 2250 Amps and their relative CCA vary from 8.6 to 12 CCA Amps per pound of battery.

Similarly, Marine Cranking Amps (MCA) or Cranking Amps (CA) vary between 10.7 and 14.5 Amps per pound.

Note: some manufacturers don't state CCA/MCA values for their batteries - these models should be used only for deep cycle applications.

Relative Reserve Capacity (RC) vary from 2.7 to 4.7 minutes per pound of the AGM/Gel-Cell battery and for GreenLIFE GL260, it is 7.8 minutes per pound of battery.

Length of warranty depends on the model and it is commonly 1-2 years, although GreenLIFE GL260 comes with 5 year warranty.

Also, warranty conditions and terms vary, and in some cases, length of warranty depends on the battery use - for example Odyssey 8D-1500 comes with 2-year warranty when used as cranking battery and 3-year warranty when used in standby applications. Again, read the warranty terms, especially so-called 'small letters' :)

Number of cycles depends on the Depth of Discharge (DoD) and acceptable capacity loss. Generally, 20% capacity loss (capacity drop down to 80% of nominal capacity of the new battery) is acceptable, but sometimes manufacturers state just number of cycles, without actual capacity loss.

50% or 80% DoD is good measure when trying to find out how good (or bad) is the battery when used in deep cycle applications - down to 80% of nominal capacity.

Most 8D batteries tolerates up to 500 charging/discharging cycles, down to 50% DoD with acceptable capacity drop down to 80% of nominal capacity, with some models being able to withstand up to 800 cycles (again, 50% DoD, down to 80% capacity).

GreenLIFE GL260 and similar lithium batteries cost 3-4 times more, but they support 3000+ cycles, some even up to 7000 cycles (50% DoD, down to 80-90% of nominal capacity).

GreenLIFE GL260 Lithium Iron Phosphate LiFePO4 Group 8D Battery

greenlife gl260GreenLIFE GL260 is designed as 'drop-in' replacement for deep cycle lead-acid batteries (flooded, AGM, Gel-Cell).

It weighs only 80 pounds (~36.3 kg), features nominal capacity of 260 Ah, and is able to provide 20 Amps for 780 minutes, 25 Amps for 624 minutes, 50 Amps for 312 minutes.

Its self discharge rate is less than 3% per month, nominal voltage of 13.4 volts and charging voltage of 14.4 - 14.6 volts.

GreenLIFE GL260 safety features include built-in internal battery protection system (BPS), automatic low-voltage (10.5 volts) disconnect system, automatic short circuit protection system, automatic over voltage protection (15.8 volts), internal cell thermal safety fuse, flame retardant electrolyte, automatic internal cell balancing, automatic fault recovery, explosion proof stainless steel cells etc.

GreenLIFE GL260 costs 3-4 times more than 'common' group 8D battery, but it tolerates 3000-5000 cycles and comes with 5-year warranty - initially, it does cost more, but in the long run, it is actually cheaper.

GreenLIFE GL260 is especially suitable for applications where total battery (or battery pack) is important like electric vehicles, RVs, robotics, telecommunications, boats/kayaks and similar.

Despite being rather expensive battery, it is relatively popular and sometimes out of stock.

For more reviews and recommendations, check GreenLiFE GL260 Amazon link (link opens in the new window).

Mighty Max ML8D AGM 12V 250Ah Deep Cycle Battery

mighty max ml8dMighty Max ML8D offers large capacity at acceptable price and is not suitable as starting/cranking battery.

Capacity of the Mighty Max ML8D battery depends on the discharge rate:

- 100 hours, 1.80 volts per cell (10.8 volts battery): 269 Ah
- 24 hours, 1.80 volts per cell (10.8 volts battery): 250 Ah
- 10 hours, 1.75 volts per cell (10.5 volts battery): 245 Ah
- 5 hours, 1.75 volts per cell (10.5 volts battery): 201.5 Ah
- 1 hour, 1.60 volts per cell (9.6 volts battery): 162.5 Ah

Its maximum (5 sec) discharge current is 1100 Amps and short circuit current is 4300 Amps.

Nonetheless, it is designed for deep cycle operations or for standby use - Mighty Max ML8D is able to withstand ~700 cycles, down to 50% DoD, while loss in capacity is not known.

Mighty Max ML8D is general purpose, deep cycle/standby group 8D battery that comes with nice price tag.

For more information about this battery, check Mighty Max ML8D Amazon link (link opens in the new window).

 NorthStar NSB-AGM8D AGM 12V Dual Purpose Battery

northstar nsb agm8dNorthStar NSB-AGM8D is true dual purpose group 8D battery, that comes in two versions labeled as NorthStar NSB-AGM8D and NorthStar NSB-AGM8DS - both models feature practically the same performances and differ in terminals:

- NorthStar NSB-AGM8D: SAE terminal posts'

- NorthStar NSB-AGM8DS: threaded terminal posts.

Anyway, NorthStar NSB-AGM8D features 220 Ah nominal capacity and only 1.7 mΩ internal resistance (at 77°F, 25°C) and is able to provide 1450 CCA and 1800 CCA.

Also, its Reserve Capacity value is 500 minutes.

With 3-year warranty and acceptable weight of 152 pounds, NorthStar NSB-AGM8D is really one of the strongest group 8D batteries on the market.

For more reviews and recommendations, check NorthStar NSB-AGM8D Amazon link (link opens in the new window).

NorthStar SMS-AGM8DK AGM 12V Dual Purpose Battery

northstar sms agm8dkNorthStar SMS-AGM8DK features best starting characteristics of all group 8D batteries listed in this article, but it also features 228 Ah nominal capacity and 500 min Reserve Capacity.

NorthStar SMS-AGM8DK batteries come in three versions, differing practically only in terminals:

- NorthStar SMS-AGM8DK: SAE terminal posts

- NorthStar SMS-AGM8DK-DT: SAE + Drop terminal posts,

- NorthStar SMS-AGM8DK-S: Threaded terminal posts.

Regardless of the terminal posts type, NorthStar SMS-AGM8DK features 2250 Amps CCA, 2700 Amps MCA, and short circuit current of 7500(!) Amps.

NorthStar SMS-AGM8DK has the 'honor' of being the heaviest of all group 8D batteries listed in this article, but it is large, strong and sturdy battery.

One of very interesting features is that NorthStar SMS-AGM8DK comes as a kit, consisting of three group 24 batteries that are connected/assembled on their permanent position - personally, it is much easier to carry around individual 24 group batteries than one 187 pounds heavy group 8D battery.

If you are looking for dual purpose group 8D battery with excellent CCA/MCA values, and you don't mind paying some extra more money, consider NorthStar SMS-AGM8DK battery.

 Odyssey 8D-1500 AGM 12V Deep Cycle Battery

odyssey 8d 1500Odyssey 8D-1500 is relatively lightweight group 8D battery featuring 475 min Reserve Capacity, 220 Ah capacity, and weighing 'just' 143 pounds.

But, it is actually excellent dual purpose battery, being able to provide 1500 Amps CCA and 1787 Amps MCA - considering its weight, it is excellent both starting and deep cycle battery being able to withstand ~750 cycles down to 50% DoD and 80% of nominal capacity.

 Odyssey 8D-1500 and NorthStar NSB-AGM8D are two very similar batteries regarding their performances:

- Odyssey 8D-1500 is somewhat lighter (143 vs 152 pounds),

- same nominal capacity of 220 Ah,

- in tradition with other Odyssey batteries, Odyssey 8D-1500 is better low temperatures performer (1500 vs 1450 CCA) and very similar performer at higher temperatures (1787 vs 1800 MCA),

- NorthStar NSB-AGM8D features slightly better RC (500 vs 475 minutes).

As one can see, these batteries are evenly matched, so go for the one which is on sale, unless you need low-temperature battery, in which case, go for Odyssey 8D-1500.

 UPG 45964 UB8D 12V 250 Ah AGM Group 8D Battery

upg 45964 ub8dUPG 45964 UB8D is deep cycle group 8D AGM battery, featuring nominal capacity of 250 Ah, and weigh 158.3 pounds (some official sources claim 154 pounds, but that is the weight of UPG 40702 UB8D Gel-Cell Group 8D deep cycle battery).

Its 10h capacity is 232.5 Ah, 5h capacity is 212.5 Ah and 1h capacity is 150 Ah, making it very nice deep cycle performer, especially considering the price.

UPG 45964 UB8D is able to withstand some 450-500 cycles down to 50% DoD and still retain 80% of its nominal capacity. Also, like many other batteries, it comes with 1-year warranty.

While not even intended as cranking/starting battery, UPG 45964 UB8D is able to provide 229 Amps for 30 minutes (down to 9.6 volts) - UPG 45964 UB8D is suitable as cranking/starting battery for small gas/diesel engines and as deep cycle/standby battery for wide range of applications like security and medical systems, backups, UPS applications, solar, off-the-grid and similar.

For more reviews and recommendations, check UPG 45964 UB8D Amazon link (link opens in the new window).

 VMAXTANKS XTR8D-350 12V 350Ah Deep Cycle AGM Group 8D Battery

vmaxtanks xtr8d 350VMAXTANKS XTR8D-350 is large, sturdy and rather heavy group 8D battery, weighing 185 pounds - only 187 pounds heavy NorthStar SMS-AGM8DK is heavier than VMAXTANKS XTR8D-350 (just 2 pounds difference).

VMAXTANKS XTR8D-350 is labeled as deep cycle battery, but it is actually excellent dual purpose battery:

- 20h capacity of 350(!) Ah - other batteries are at most in 250-260 Ah range,

- 780 minutes Reserve Capacity - other batteries are at most near 600 minutes,

- 1700 CCA and 2100 MCA - NorthStar SMS-AGM8DK features 2250 CCA and 2700 MCA, but it costs more and is not as nearly good as deep cycle battery as VMAXTANKS XTR8D-350 is good as starting battery!

VMAXTANKS XTR8D-350 features both SAE and 3/8" stud terminals, can withstand some 800 cycles down to 50% DoD and still retain 80% of nominal capacity.

Obviously, VMAXTANKS XTR8D-350 generally costs more than other 8D group 220-250 Ah batteries, but its capacity is ~30 - 40% larger, it is dual purpose battery, can cycle ~800 times (50% DoD, 80% capacity) and can store and provide large amounts of energy.

For most up-to-date prices and offers, check VMAXTANKS XTR8D-350 Amazon link (link opens in the new window).

The Best 8D Deep Cycle Battery - Pick the Right One

Considering all that has been said, the best deep cycle battery is VMAXTANKS XTR8D-350 even when considering its price.

However, if you need group 8D battery and performances of VMAXTANKS XTR8D-350 are a slight overkill, feel free to consider other batteries as well:

Compare the prices:

For example, Mighty Max ML8D, Renogy AGM12-200 and GEL12-200, UPG 45964 UB8D are cheaper options, especially when considering only deep cycle and standby applications.

Long Story Short: Many battery brands manufacture AGM and Gel-Cell group 8D batteries, which are used in various types of applications. Even batteries intended only for deep cycle applications are able to provide large currents and are used in off-the-grid, solar, backup, security and similar applications.

Nonetheless, there are few models whose features stand out, so be sure to choose according to your own needs and preferences.