| |
My Battery Always Dies - Part 3 Sizing your Battery for Your Accessories
Previous : My Battery Always Dies - Part 2 Scenarios Where Your Battery May Die!
Next: My Battery Always Dies - Part 4 Checking the Sizes of Fuses, Overcurrent Protection
The million dollar question is always "What Battery Then?"
The answer in real world scenarios become very intricate.
We have chosen to look at a few methods for increasing your battery capacity below.
First we will look at the basics, overview an easy upgrade method, and then get into loads and calculations based on those loads.
Part 1: Examine your battery
First order of business in upgrading your battery is to figure out what you have already (assuming you have a battery). Go to your vehicle and examine the battery. You should see some of the following specifications listed, we include a definition as well:
V = voltage
cca = Cold cranking amps
Corresponds to 0° Cranking Amps for 15 seconds
ca = Cranking amps (different than CCA)
Corresponds to 32° Cranking Ampsfor 15 seconds
ah = ampere hours
amps x hours, 6ah = 2hr x 3amp at specified voltage.
Higher amperages incur friction losses, different discussion
pn = part number, (Secret, it usually has a bci code in it)
BCI codes are common battery sizes from any and all manufacturers set by the Battery Council International. The table of part numbers to the right and their sizes are standards.
Please take note of this too:
The type of battery; flooded, sealed, agm, or gel.
Measurements of the battery; height, width, depth
If you don't deal well with fractions, use mm measurements.
Armed with this basic information, you can now begin to determine what you have, how it is working currently for YOU, and what you want it to do. We will call this the basic method of upgrading your vehicle's battery bank.
HOUSE BANKS: By this point you know if you have 1 or 2 banks of batteries, usually RVs, boats, ambulances, and some police vehicles have the second bank. These too are upgradeable, but we will focus on the starting battery for this discussion.
Part 2: Decide your Application, Usage, and Need
First order of business after you have your specifications in hand is to find a computer and log on to the
All batteries by Capacity at page BDBatteries.com
OR
All batteries by Size at page BDBatteries.com.
Once you are in, you will be able to order all batteries in the inventory by capacity. Remember to select a battery with at least the same CCA, CA, and AH as the one that came stock in the vehicle. This will ensure you have adequate power to start the vehicle.
Feel free to use "Deep Cycle" batteries as starting batteries as long as they have sufficient CCA or CA for your application, they will work fine. The added AH will dramatically help your accessories, and is the point of this article.
Part 3: Based on Chemistry do you get of Jail Free?
Did you find a battery with more AH, CA, and CCA with less weight and size? YOUR AREN'T ALONE.
Every type of lead acid battery is basically built with the same materials. However, the method in which the battery is manufactured dictates it's effeciency, lifespan, and general value. A tradeoff of quality is obviously associated with price, but there is another issue in play here, efficiency and types of batteries....
Flooded Batteries
Generally stock batteries are flooded starting batteries. The flooded lead acid battery has been around for nearly 100 years and they work great. Unfortunately, they need maintenance though, they corrode, make a mess, need water, and are as low as 50% efficient at high current loads (Deep Cycle flooded), or have relatively low AH ratings (SLI flooded). By simply upgrading to an AGM product you could gain over 50% of the amperage efficiency, and dramatically increase the AH. The AGM battery construction is simply more efficient, which means more power for your toys in the same space by switching to an AGM battery.
Gel Batteries
If you have a Gel battery, you are restricted to lower amps or you may damage the battery. By loading a Gel Battery up with high current you run the risk of scaring or liquifying the gel that holds the electrolyte in place. Again, not the answer when you are adding more toys to the system.
AGM Batteries
The higher technology used in manufacturing the battery results in a higher price, but the output of the product is the benefit. High quality AGM batteries boast the same cycle lives of flooded models, and are far more efficient. Simply compare the engineering specifications of the lifeline or optima and a battery from your local superstore. Remember, AGM Batteries produced in the UNITED STATES are superior to those imported based on cycle life, and ah per lb.
A more complete battery comparison.
Part 3a: Based on Chemistry do you get of Jail Free? --> YES
Since you have a Gel or Flooded starting battery under your hood, and you only want a bit more juice, you simply find the battery in the list to the left.
----- ----- ----- ----- ----- ----- ----- ----- ----- ----->>>
Next, find the Optima or Lifeline Battery that is sized to fit your own (worst case: an inch or two different by using this page).
All Motive AGM Batteries from BD Batteries by Size
Once you have selected the battery based on Size and AH, ensure you have the CCA or CA for your engine as a final check. By switching to an Optima, you get the efficiency, with approximately the same weight by volume (circles of lead do not completely fill the case, there are voids). If you choose to upgrade to a Lifeline Starting battery you get more CCA, more AH, and more efficiency in roughly the same area. Usually this upgrade is the equivalent of adding another battery in the same area.
Lifeline Deep Cycle batteries can be used in lieu of a starting battery if you upsize or add another battery to compensate for the CCA requirement to start your engine. You get more AH, and adequate CCA when you decide to replace with deep cycle batteries, but these are absolutely the answer for Audio Drag Racing, repeated winch operation, sustained accessories application (ambulances for instance) and other extended amperage draw situations (inductive loads).
Lifeline High Performance AGM Batteries
Optima Yellow Top High Performance Batteries
Part 3b: Based on Chemistry do you get of Jail Free? --> NO
If you already have an AGM battery, and are still using all your power, we need to add more batteries, or increase the size of the battery bank to accommodate your needs.
At this point, several of you will roughly gauge the amount of time it takes to run your battery dry, and then add another, 2 or 3 more batteries according to rough math. For instance, you can run your stereo full blast with the lights on every friday at the park for flag football for 1 hour. Problem is you NEED 2 hours, and you are sick of buying batteries once a month.
THE ANSWER:
To double your run time, you double the battery pack. (1 goes to 2 hours of operation).
To make the batteries last, you double again, and buy quality batteries. (2 goes to 4 batteries).
WHY ==> When you drain your battery fully, you reduce the lifespan by default. Full discharge is terribly hard on the battery, as you must force the reaction to start from scratch. This requires a bit of time on the charger, and that hurts your battery. Batteries are designed to run down 20% (for flooded or AGM starting batteries), 50% (for AGM Deep Cycle Batteries), or 80% (for flooded deep cycle batteries). Basically that is 1/5, 1/2, and 4/5 of capacity respectively. The difference is 500-1000 cycles vs 1-200, depending on the specs of the battery.
Graph of lifeline battery cycles and depth of discharge.
Notice 1000 cycles at 50% DOD
Logically, the next question is then;
So why are AGM's better than flooded deep cycle batteries?
4 reasons:
1, NO MAINTENANCE. Flooded lead acid batteries require watering, or the plates will be oxidized by the air around them. AGM Batteries require no watering or reservoir.
2, NO MESS. Flooded lead acid batteries are prone to gassing sulphuric acid. This acid corrodes the terminals, wires, and other parts surrounding the battery. AGM Batteries will not corrode their surroundings.
3, SAFER. Flooded lead acid batteries are not sealed so you can add water to them. However, if toppled, they leak a Hazardous Material, strong sulphuric acid that will eat through carpet, tile, linoleum, and other nice things including concrete. AGM Batteries are non-spillable, per the DOT (U.S. Department of Transportation), and are able to be shipped with normal freight.
4, HIGHER AMPS, Compared to flooded deep cycle batteries, AGM Deep cycle batteries provide more current (Cold Cranking Amps) due to their lower internal resistance. This lack of resistance leads to a better hybrid battery composition for dual use applications (accessories, and vehicle starting) than elder flooded models.
Part 3c: The Math as Promised.
Okay lets look at 2 examples of usage of a vehicle battery. We need to then put batteries in the vehicle to match.
Example A: Diesel Truck, wants to run an alarm on both truck and trailer. While truck is off, the car alarm system draws roughly 2/3 of an amp. (.65 amps at 12 volts). The guy has a battery in his truck with 45 AH, 900 CCA, and is a size 31 flooded lead acid battery. When the guy goes on vacation (a week, 7 days), he comes back to a dead battery. In addition, upon record scrutiny, he had bought a battery every 7 months since the alarm was installed. He vacations bi-monthly. WHAT IS GOING ON? WHY IS MY BATTERY DEAD?
The alarm is on for 7 days, or 168 hours (7*24 hours).
For each hour it burns .65 amps at 12 volts, or .65ah at 12 volts.
His battery only holds 45 ah of juice when fully charged.
45AH divided by .33A ~ 136 hours (amps cancel out)
136 hours is not 168 hours, result, dead battery every time.
TO FIX IT;
Time you need (168 hours), multiplied by
Juice you burn (.65 amps), multiplied by
Depth of Discharge (2 - invert fractions above - 1/2 for Deep Cycle AGM Battery)
168*.65 * 2 ~ 218.4 AH of battery
1 GPL-4D has the AH, but not the CCA.
2 GPL-31Ts have the AH (220) and the CCA (1200) when hooked up in parallel, ++ and --
Example B: Real Estate Agent, wants to run a laptop, printer, A/C, GPS, cellphone, refrigerator, stereo (upgraded) and a few other gadgets at the same time, for hours at a time, while driving clients to see properties (roughly 8 hours of showings per day). The agent stops multiple times in a row when properties are close, less frequently when placed across town. She has installed a basic 1000 watt inverter to power the electronics not able to run through the cigarette lighter like her printer, but she rarely uses it. She has a high output, high amperage alternator, but sometimes she can't start the car. WHAT IS GOING ON? WHY IS MY BATTERY DEAD?
WOW, lots to work with here. I still haven't figured out how she runs it all at once and drives, but no matter. (My response was: "How do you run all your toys at once?" She laughed.)
To start this problem, we need to know the outputs, or at least get a rough idea.
She says that the inverter she has tells her what kind of output she is using (% basis) and that is runs at roughly 5-20% load, for sake of argument, we will ignore it below.
We know these, and this tackles most of the problem:
12v 1.5 amp cellphone
12v 20 amp cooler
12v 6 amp laptop
12v 1 amp gps
12v 83 amps (1000 watt amplifier)
12v 12 amps (upgraded stereo)
We also know the vehicle needs to run it's displays, blinkers, break lights, etc. so we will assume another 40 more for her small car, and this can pick up the % from the inverter above as well.
Remember, she upgraded from a 65 amp alternator to a 100 amp one.
Let's run her numbers, 123.8 amps minimum, 163.8 amps maximum.
Wonder why her battery gives out?
TO FIX IT;
Time you need (8 hours), multiplied by
Juice you burn (average of 123 and 163 = 143.8 amps) = 1150.4 AH.
We then subtract what the alternator can contribute in a perfect world.
Time (8 hrs) x output (100 amps) = 800 AH.
Total (1150.4 ah) - alternator (800 ah) = battery cap reqd (310 ah)
Again multiply battery cap by 2 for Depth of Discharge
(inverted fraction from above - deep cycle agm batteries)
Result was 610 AH.
When apprised with the math, the client opted to remove the refrigerator and try again.
Time you need (8 hours), multiplied by
Juice you burn (average of 123 and 163 = 143.8 amps - 20 amps for fridge or 123.8) = 990.4 AH.
We then subtract what the alternator can contribute in a perfect world.
Time (8 hrs) x output (100 amps) = 800 AH.
Total (990.4 ah) - alternator (800 ah) = battery cap reqd (190 ah)
Again multiply battery cap by 2 for Depth of Discharge
(inverted fraction from above - deep cycle agm batteries)
Result was 400 AH, she installed 4 GPL-27s in her truck, vented them, and is selling houses.
Even now!
Part 4: Where do I put em, and how?
Installing another battery under your hood is relatively easy. All you need is something flat to bolt to.
AGM batteries can be installed at any angle, upside down if you like, and this accomodates many an interesting install. JUST MAKE SURE THEY ARE WELL SUPPORTED. The other thing to worry about is gases, all lead acid batteries gas, GEL, AGM, and Flooded too. So vent your batteries if you put them in a closed space.
Internal Installs:
The obvious locale for adding batteries is under the hood, in any space not used by something else. We carry a range of battery hold down kits, metallic automotive battery boxes, and battery hold down kits for this purpose.
External Installs:
Many folks install them on the bumper, under the pickup bed, or in other exposed areas outside the engine compartment. We suggest a flat space, with one of our battery boxes to protect the cargo inside from the road grime for these installs.
Plastic Battery Boxes
|
Common Battery Sizes -
Switch to a Deep Cycle AGM Battery |
| BCI Size & Model |
L in / mm |
W in / mm |
H in / mm |
| BCI Group 1 Battery |
9.13
inches /
232mm |
7.13
inches /
181mm |
9.38
inches /
238mm |
| BCI Group 17HF Battery |
7.38
inches /
187mm |
6.88
inches /
175mm |
9.00
inches /
229mm |
| BCI Group 2 Battery |
10.38
inches /
264mm |
7.13
inches /
181mm |
9.38
inches /
238mm |
| BCI Group 21 Battery |
8.19
inches /
208mm |
6.81
inches /
173mm |
8.75
inches /
222mm |
| BCI Group 22F Battery |
9.50
inches /
241mm |
6.88
inches /
175mm |
8.31
inches /
211mm |
| BCI Group 22HF Battery |
9.50
inches /
241mm |
6.88
inches /
175mm |
9.00
inches /
229mm |
| BCI Group 22NF Battery |
9.44
inches /
240mm |
5.50
inches /
140mm |
8.94
inches /
227mm |
| BCI Group 22R Battery |
9.00
inches /
229mm |
6.88
inches /
175mm |
8.31
inches /
211mm |
| BCI Group 24 Battery |
10.25
inches /
260mm |
6.81
inches /
173mm |
8.88
inches /
225mm |
| BCI Group 24F Battery |
10.75
inches /
273mm |
6.81
inches /
173mm |
9.00
inches /
229mm |
| BCI Group 24H Battery |
10.25
inches /
260mm |
6.81
inches /
173mm |
9.38
inches /
238mm |
| BCI Group 24R Battery |
10.25
inches /
260mm |
6.81
inches /
173mm |
9.00
inches /
229mm |
| BCI Group 24T Battery |
10.25
inches /
260mm |
6.81
inches /
173mm |
9.75
inches /
248mm |
| BCI Group 25 Battery |
9.06
inches /
230mm |
6.88
inches /
175mm |
8.88
inches /
225mm |
| BCI Group 26 Battery |
8.19
inches /
208mm |
6.81
inches /
173mm |
7.75
inches /
197mm |
| BCI Group 26R Battery |
8.19
inches /
208mm |
6.81
inches /
173mm |
7.75
inches /
197mm |
| BCI Group 27 Battery |
12.06
inches /
306mm |
6.81
inches /
173mm |
8.88
inches /
225mm |
| BCI Group 27F Battery |
12.50
inches /
318mm |
6.81
inches /
173mm |
8.94
inches /
227mm |
| BCI Group 27H Battery |
11.75
inches /
298mm |
6.81
inches /
173mm |
9.25
inches /
235mm |
| BCI Group 28 Battery |
10.31
inches /
261mm |
6.81
inches /
173mm |
9.44
inches /
240mm |
| BCI Group 29H Battery |
13.13
inches /
334mm |
6.75
inches /
171mm |
9.00
inches /
232mm |
| BCI Group 29NF Battery |
13.00
inches /
330mm |
5.50
inches /
140mm |
8.94
inches /
227mm |
| BCI Group 2E Battery |
19.44
inches /
492mm |
4.13
inches /
105mm |
9.13
inches /
232mm |
| BCI Group 2N Battery |
10.00
inches /
254mm |
5.56
inches /
141mm |
8.94
inches /
227mm |
| BCI Group 30H Battery |
13.50
inches /
343mm |
6.81
inches /
173mm |
9.00
inches /
235mm |
| BCI Group 31 Battery |
13.00
inches /
330mm |
6.72
inches /
173mm |
9.44
inches /
240mm |
| BCI Group 33 Battery |
13.31
inches /
338mm |
6.81
inches /
173mm |
9.38
inches /
238mm |
| BCI Group 34 Battery |
10.25
inches /
260mm |
6.81
inches /
173mm |
7.88
inches /
200mm |
| BCI Group 34R Battery |
10.25
inches /
260mm |
6.81
inches /
173mm |
7.88
inches /
200mm |
| BCI Group 35 Battery |
9.06
inches /
230mm |
6.88
inches /
175mm |
8.88
inches /
225mm |
| BCI Group 36R Battery |
10.38
inches /
263mm |
7.25
inches /
183mm |
8.13
inches /
206mm |
| BCI Group 40R Battery |
10.94
inches /
277mm |
6.88
inches /
175mm |
6.88
inches /
175mm |
| BCI Group 41 Battery |
11.19
inches /
293mm |
6.88
inches /
175mm |
6.88
inches /
175mm |
| BCI Group 42 Battery |
9.31
inches /
243mm |
6.81
inches /
173mm |
6.81
inches /
173mm |
| BCI Group 43 Battery |
13.13
inches /
334mm |
6.88
inches /
175mm |
8.06
inches /
205mm |
| BCI Group 45 Battery |
9.44
inches /
240mm |
5.50
inches /
140mm |
8.94
inches /
227mm |
| BCI Group 46 Battery |
10.75
inches /
273mm |
6.81
inches /
173mm |
9.00
inches /
229mm |
| BCI Group 47 Battery |
9.69
inches /
246mm |
6.88
inches /
175mm |
7.50
inches /
190mm |
| BCI Group 48 Battery |
12.06
inches /
306mm |
6.88
inches /
175mm |
7.56
inches /
192mm |
| BCI Group 49 Battery |
15.00
inches /
381mm |
6.88
inches /
175mm |
7.19
inches /
192mm |
| BCI Group 4D Battery |
20.75
inches /
527mm |
8.75
inches /
222mm |
9.88
inches /
250mm |
| BCI Group 50 Battery |
13.50
inches /
343mm |
5.00
inches /
127mm |
10.00
inches /
254mm |
| BCI Group 51 Battery |
9.38
inches /
238mm |
5.06
inches /
129mm |
8.81
inches /
223mm |
| BCI Group 51R Battery |
9.38
inches /
238mm |
5.06
inches /
129mm |
8.81
inches /
223mm |
| BCI Group 52 Battery |
7.31
inches /
186mm |
5.81
inches /
147mm |
8.25
inches /
210mm |
| BCI Group 53 Battery |
13.00
inches /
330mm |
4.69
inches /
119mm |
8.25
inches /
210mm |
| BCI Group 54 Battery |
7.31
inches /
186mm |
6.06
inches /
154mm |
8.38
inches /
212mm |
| BCI Group 55 Battery |
8.63
inches /
218mm |
6.06
inches /
154mm |
8.38
inches /
212mm |
| BCI Group 56 Battery |
10.00
inches /
254mm |
6.06
inches /
154mm |
8.38
inches /
212mm |
| BCI Group 57 Battery |
8.06
inches /
205mm |
7.19
inches /
183mm |
6.94
inches /
177mm |
| BCI Group 58 Battery |
10.06
inches /
255mm |
7.19
inches /
183mm |
6.94
inches /
177mm |
| BCI Group 58R Battery |
10.06
inches /
255mm |
7.19
inches /
183mm |
6.94
inches /
177mm |
| BCI Group 59 Battery |
10.06
inches /
255mm |
7.63
inches /
193mm |
7.75
inches /
196mm |
| BCI Group 60 Battery |
13.06
inches /
332mm |
6.31
inches /
160mm |
8.88
inches /
225mm |
| BCI Group 61 Battery |
7.56
inches /
192mm |
6.38
inches /
162mm |
8.88
inches /
225mm |
| BCI Group 62 Battery |
8.88
inches /
225mm |
6.38
inches /
162mm |
8.88
inches /
225mm |
| BCI Group 63 Battery |
10.19
inches /
258mm |
6.38
inches /
162mm |
8.88
inches /
225mm |
| BCI Group 64 Battery |
11.69
inches /
296mm |
6.38
inches /
162mm |
8.88
inches /
225mm |
| BCI Group 65 Battery |
12.06
inches /
306mm |
7.50
inches /
190mm |
7.56
inches /
192mm |
| BCI Group 6D Battery |
20.75
inches /
527mm |
10.00
inches /
254mm |
10.25
inches /
260mm |
| BCI Group 70 Battery |
8.19
inches /
208mm |
7.06
inches /
179mm |
7.69
inches /
196mm |
| BCI Group 71 Battery |
8.19
inches /
208mm |
7.06
inches /
179mm |
8.50
inches /
216mm |
| BCI Group 72 Battery |
9.06
inches /
230mm |
7.06
inches /
179mm |
8.25
inches /
210mm |
| BCI Group 73 Battery |
9.06
inches /
230mm |
7.06
inches /
179mm |
8.50
inches /
216mm |
| BCI Group 74 Battery |
10.25
inches /
260mm |
7.25
inches /
184mm |
8.75
inches /
222mm |
| BCI Group 75 Battery |
9.06
inches /
230mm |
7.06
inches /
179mm |
7.69
inches /
196mm |
| BCI Group 76 Battery |
13.13
inches /
334mm |
7.06
inches /
179mm |
8.50
inches /
216mm |
| BCI Group 78 Battery |
10.25
inches /
260mm |
7.06
inches /
179mm |
7.69
inches /
196mm |
| BCI Group 85 Battery |
9.06
inches /
230mm |
6.81
inches /
173mm |
8.00
inches /
203mm |
| BCI Group 86 Battery |
9.06
inches /
230mm |
6.81
inches /
173mm |
8.00
inches /
203mm |
| BCI Group 8D Battery |
20.75
inches /
527mm |
11.13
inches /
283mm |
9.88
inches /
250mm |
| BCI Group 90 Battery |
9.69
inches /
246mm |
6.88
inches /
175mm |
6.88
inches /
175mm |
| BCI Group 91 Battery |
11.00
inches /
280mm |
6.88
inches /
175mm |
6.88
inches /
175mm |
| BCI Group 92 Battery |
12.50
inches /
317mm |
6.88
inches /
175mm |
6.88
inches /
175mm |
| BCI Group 93 Battery |
15.00
inches /
354mm |
6.88
inches /
175mm |
6.88
inches /
175mm |
| BCI Group 95R Battery |
15.56
inches /
394mm |
6.88
inches /
175mm |
7.50
inches /
190mm |
| BCI Group 96R Battery |
9.56
inches /
242mm |
6.81
inches /
173mm |
6.88
inches /
175mm |
| BCI Group 97R Battery |
9.94
inches /
252mm |
6.88
inches /
175mm |
7.50
inches /
190mm |
| BCI Group 98R Battery |
11.19
inches /
283mm |
6.88
inches /
175mm |
7.50
inches /
190mm |
| BCI Group GC2 Battery |
10.38
inches /
264mm |
7.19
inches /
183mm |
10.63
inches /
270mm |
| BCI Group GC2H Battery |
10.38
inches /
264mm |
7.19
inches /
183mm |
11.63
inches /
295mm |
|
If you find this helpful, Digg, Del.icious, blog, or drop us a line about it.
BD Batteries
Previous : My Battery Always Dies - Part 2 Scenarios Where Your Battery May Die!
Next: My Battery Always Dies - Part 4 Checking the Sizes of Fuses, Overcurrent Protection
Legally: REMEMBER, ELECTRICITY HURTS, IT CAN KILL YOU. BD BATTERIES TAKES NO RESPONSIBILITY FOR YOUR ACTIONS WITH THIS INFORMATION. IF YOU AREN'T TRAINED TO WORK WITH ELECTRICITY, CALL SOMEONE WHO IS. IF YOU CHOOSE TO MEDDLE, YOU AGREE TO TAKE RESPONSIBILITY FOR YOURSELF! THIS GUIDE IS IN NO WAY A COMPLETE ELECTRICAL GUIDE, AND SHALL NOT BE PRESENTED AS SUCH IN ANY FORMAT OR FORUM. PERFORMANCE BATTERIES ARE CAPABLE OF ARC WELDING STEEL AND OTHER VERY INTERESTING THINGS INCLUDING YOUR HEART. BE CAREFUL, DON'T HURT YOURSELVES.
|
|
|
