BCI Group 4D and 8D Batteries - Features and Specifications

BCI Group 4D and 8D batteries are large and heavy lead-acid batteries, that can store large amounts of energy and release it in both short but strong energy bursts or slowly, over longer periods of time.

BCI Group 4D and 8D batteries are not used as often as smaller batteries from BCI groups 31, 24, or 27, but are nonetheless very popular in automotive, industrial and marine applications where strong and reliable batteries are required.

renogy 200ah 4d agm battery

BCI Group 4D and 8D batteries are very similar to BCI Group 6D batteries in size and features, but interestingly, not many battery brands make batteries labeled as '6D' although there are several battery models labeled as '4D' that are too large to be actual '4D' battery and there are several battery models labeled as '8D' batteries that are very close to '6D' size.

Anyway, whenever getting new batteries, especially the batteries of this size and price, be sure to check actual battery size, battery terminals type, and orientation and the size of your battery compartments, and length of cables.

Physical dimensions of BCI Group 4D, 6D and 8D batteries are given in the following list (L x W x H):

- BCI Group 4D: 20.75 x 8.75 x 9.875 inches (527 x 222 x 250 mm)

- BCI Group 6D: 20.75 x 10 x 10.25 inches (527 x 254 x 260)

- BCI Group 8D: 20.75 x 11.125 x 9.875 inches (527 x 283 x 250 mm).

Due to their dimensions, BCI Group 4D and 8D batteries feature nominal (20h) capacity usually in the 170-350 Ah range, with CCA rating of 1200-1500 Amps (if labeled) and with typical RC value of 350-780 minutes.

But, such performances come with some serious weight penalty, at least for lead-acid batteries - BCI Group 4D and 8D batteries are rather heavy batteries with their weight ranging from 115 to 185 pounds (~52 to 84 kg) for lead-acid batteries and 68 to 80 pounds (~30 to 36 kg) for lithium-ion batteries.

Most of 4D and 8D batteries feature carrying handles, but due to their weight, it is not recommended - place them on a suitable cart or similar device and transport from one place to another.

The following comparison chart lists some of the most popular 4D and 8D AGM, Gel and Lithium-ion batteries on the market:

Model Battery Type Chemistry Ah CCA MCA RC Weight (lbs/kg) Dimensions
(LxWxH, inches)
Review
AIMS Power LFP12V200A Deep Cycle LiFePO4 200 (2h) - - ~480 68.8 lbs; 31.1 kg 19.38 x 10.5 x 8.75 -
Concorde PVX 2580L Deep Cycle AGM 258 - - 480 (@29.5 Amps) 159 lbs; 72.1 kg 20.76 x 10.22 x 9.77 -
Deka 8A4D Deep Cycle AGM 198 1110 - 380 129 lbs; 58.5 kg 20.75 x 8.5 x 10 -
Deka Gel-8G4D Deep Cycle Gel 183 970 - 395 127 lbs; 57.6 kg 20.75 x 8.5 x 10 -
Deka AGM 8A8D Deep Cycle AGM 245 1450 - 517 158 lbs; 71.6 kg 20.75 x 11 x 10 -
Deka Gel-8G8D Deep Cycle Gel 225 1150 1470 500 157 lbs; 71.2 kg 20.75 x 11 x 10 -
ExpertPower EXP122000 Deep Cycle AGM 220 - - 600 (@20 Amps) 132.3 lbs; ~60 kg 20.59 x 9.44 x 8.62 -
Fullriver DC260-12 Deep Cycle AGM 260 1525 1830 578 170.6 lbs; ~77 kg 20.51 x 10.59 x 8.82 -
GreenLiFE GL260-260AH Deep Cycle LiFePO4 260 - - 624 80 lbs; 36.24 kg 20.44 x 10.57 x 8.7 -
LifeLine GPL-4DL Deep Cycle AGM 210 1100 1360 390 124 lbs; 56.2 kg 20.76 x 8.7 x 8.64 -
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 ML4D Deep Cycle AGM 200 - - ~360 114.6 lbs; ~52 kg 20.9 x 8.23 x 8.46 Mighty Max ML4D
Mighty Max ML8D Deep Cycle AGM 250 - - 600 (@24.5 Amps) 159 lbs; 72.0 kg 20.47 x 10.55 x 8.66 -
PowerStar PS200-12 Deep Cycle AGM 200 - - - 135 lbs; 61.2 kg 20.55 x 9.37 x 8.58 -
Renogy RNG-BATT-AGM12-200 Deep Cycle AGM 200 - - ~600 (@20 Amps) 129 lbs; 58.5 kg 20.50 x 9.4 x 9.4 -
Renogy RNG-BATT-GEL12-200 Deep Cycle Gel 200 - - ~600 (@20 Amps) 128 lbs; ~ 58 kg 20.60 x 9.5 x 8.7 -
Renogy RBT200GEL12-G1 Deep Cycle Gel 200 - - ~600 (@20 Amps) 127.9 lbs; ~58 kg 20.6 x 9.4 x 8.8 -
Trojan 8D-Gel Deep-Cycle Gel 225 - - 500 168 lbs; 76 kg 20.69 x 10.95 x 10.82 -
UPG UB4D-AGM Deep Cycle AGM 200 - - ~600 (@20 Amps) 114.6 lbs; ~52 kg 21.0 x 8.15 x 8.47 -
UPG UB8D Deep Cycle AGM 250 - - 600 (@23.2 Amps) 154 lbs; 70 kg 20.47 x 10.55 x 9.65 -
VMAXTANKS MR197-200 Deep Cycle AGM 200 - 1400 450 112 lbs; ~51 kg 19.1 x 6.8 x 9.5 VMAXTANKS MR197-200
VMAXTANKS XTR4D-200 Dual Purpose AGM 200 1250 1670 470 130 lbs; ~59 kg 20.8 x 8.7 x 9.0 -
VMAXTANKS XTR8D-350 Deep Cycle AGM 350 1700 2100 780 185 lbs; 83.8 kg 20.8 x 11.1 x 9.8 -

Note: Amazon links ('Model' column) open in the new window, feel free to check them for the most up-to-date offers and prices.

As one can see, all 4D and 8D batteries are basically designed as deep cycle batteries - even the powerful VMAXTANKS XTR4D-200 is labeled as a deep cycle by their manufacturer, but thanks to its performances, it is an excellent well-balanced dual-purpose battery.

However, even they are labeled as 'deep cycle' batteries, many of these models are able to provide CCA of 1000+ Amps.

vmaxtanks xtr4d 200 battery

Note: as said before, dimensions of the batteries vary, they are not strict 4D, 6D or 8D batteries., so always check actual dimensions!

BCI Group 4D, 6D or 8D as RV House Batteries

BCI Group 4D, 6D and 8D batteries are commonly used in off-the-grid applications, powering various devices and being charged with solar panels, wind turbines or power generators.

Despite their size, these batteries are often connected in series and parallel in order to provide the required voltage or to have large enough capacity.

For example, both VMAXTANKS MR197-200 and VMAXTANKS XTR4D-200 are labeled as 4D 200 Ah batteries, but if you are making, for example, custom battery pack as RV house battery and you have enough space to fit four 4D batteries (total width ~35-36 inches) you can place either four (4) VMAXTANKS XTR4D-200 or FIVE (5) VMAXTANKS MR197-200 batteries.

- 4 (four) VMAXTANKS XTR4D-200 equals to 800 Ah 20h capacity, 6680 MCA Amps, and 520 pounds (~236 kg),

- 5 (five) VMAXTANKS MR197-200 equals to 1000 Ah 20h capacity, 7000 MCA Amps, and 560 pounds (~255 kg).

Of course, this is just an example that shows how large, heavy, but also strong these batteries are.

RV Roof Top 13.500 BTU Air Conditioner requires on average 2500 starting watts and 1600 running watts (this depends on the air conditioner class, its current settings, etc.).

Such air conditioner may be powered via 120 volts inverter (preferably pure sine inverter with less than 3% THD), being connected to the RV house battery pack.

If the inverter has 90% efficiency, that means that the battery pack must provide not 1600 running watts, but ~1800 watts.

Note: 2000 watts are 'unofficial' limit for 12 volts inverters. If you need more power, consider 24, 36, or 48 volts systems.

1800W at 12V means a current of ~ 150 Amps - and that is a lot.

Nonetheless, in theory, 1000Ah battery pack (5x VMAXTANKS MR197-200) may power such 13.000 BTU RV air conditioner for at least 5 hours, after which the batteries should be recharged.

Note: we used VMAXTANKS batteries in this example, but other brands are good as well - just be sure to check the dimensions, weight, and features of the batteries.


 BCI Group 4D, 6D or 8D as Trolling Motor Battery

mighty max ml4d agm tableBCI Group 4D and 8D batteries may be used as excellent deep cycle trolling motor batteries.

With an average 20h capacity of 200Ah for 4D batteries and a maximum 20h capacity of 350+ Ah for 8D batteries, these batteries may easily power electric trolling motors for hours.

For example, Mighty Max ML4D features 20h capacity of 200Ah (10 Amps for 20h), 5h capacity of 157.5 Ah (31.5 Amps for 5 hours), and 3h capacity of 145.2 Ah (48.4 Amps for 3 hours).

That means that if the boat has one Mighty Max ML4D battery and one 50 Amps electric trolling motor, its runtime at the full-throttle will be slightly less than 3 hours and when the throttle is at ~60% (~30 Amps), the runtime will be around 5 hours with some energy still left in the battery.

For longer runtime, consider either adding another battery in parallel, consider getting a larger battery for example, Mighty Max ML8D features 20h capacity of 250 Ah, but VMAXTANKS XTR8D-350 features 20h capacity of 350 Ah capacity!


Lithium 4D, 6D, and 8D Batteries

aims power 200ah lithiumThe main drawback of lead-acid batteries is their weight - this weight penalty is not severe in the shore/land-based off-the-grid applications, but when battery packs are made using several 4D, 6D, or 8D batteries, the weight quickly ads up.

And here is where lithium-ion batteries come to play - for the same capacity, lithium-ion batteries weigh 2-4x less than their lead-acid counterparts.

This weight advantage is even larger when the batteries are being discharged with stronger currents, when lead-acid batteries suffer from capacity loss, while lithium-ion batteries continue to perform well.

For example, Mighty Max ML4D features Reserve Capacity (25 Amps discharge current) of ~360 minutes, while AIMS Power LFP12V200A deep discharge battery features practically no capacity loss, having RC value of ~480 minutes.

Another advantage of lithium-ion batteries is their ability to recover after being deeply discharged - AIMS Power LFP12V200A feature 4000 cycles down to 100% DoD, while lead-acid batteries rarely can tolerate more than 250 charging/discharging cycles down to 100% DoD.

The initial investment into 200Ah lithium-ion batteries may be significant, but in the long run a large number of cycles and weight reduction may be a great money saver.

Note: each lithium-ion battery feature different Battery Management System (BMS) - some lithium-ion batteries may be directly connected in series, some may be directly connected in parallel, some in both parallel and series, and some models are forbidden to be connected in parallel/series. So, be very careful when choosing lithium-ion batteries for your deep cycle applications.


Long Story Short: BCI Group 4D, 6D and 8D batteries are rather heavy lead-acid batteries, but they pack a lot of energy and are commonly used in various solar, wind, off-the-grid, automotive, marine, industrial and other demanding applications.

Large, deep-cycle lithium batteries are rather expensive batteries that feature large capacity, much lower weight and much larger number of charging/discharging cycles - in the long run, they are more cost-effective than lead-acid batteries.

Again, before getting any of these batteries, check their actual size, terminal types, recommended charging methods and similar...