EverStart Marine Battery 27DC-850N is rated
Rated 4 out of
Good, versatile battery
I have used several 27N850 Everstart Marine Start and Troll batteries in my vehicles over the years, which has given me a pretty good idea on their performance strengths and weaknesses. This is perhaps not your typical use for these batteries, but it approaches it and I believe this should be helpful to determine if that battery is right for you.
In Québec at least and probably in Canada, this battery is supplied by Johnson Controls, one of the best respected battery manufacturers in the world. I understand that in the United States, it is supplied by Exide.
BASIC DESIGN AND INTENDED USE
The marketing describes exactly what they are designed for: starting, with some use while the engine is off. In other words, trips in the boat during summer with fishing and power use with engine off for a few hours, or, in my case, for starting and using my fridge and other accessories while camping or going for picnics. Although it is called a "Deep Cycle" battery, it is NOT built to be used as a power bank in power generation installations. It is simply a starting battery with slightly heavier plates for greater reserve capacity, at the cost of slightly lower starting capacity.
After 12 years, I have just purchased my third set of two batteries (my vehicle uses 2 batteries in a 24V configuration for starting and 12V running) and one for my wife's car (as she tends to forget her lights on). As I need to replace both batteries when one weakens, I have replaced them at around 6 years of age but this is an average, the weakest lasting only 3.5 years (I should have been maintaining my wife's car battery), the best about 8 years (a few more years after I removed it from my truck).
MAINTENANCE, MAINTENANCE, MAINTENANCE!
These batteries need maintenance and some basic knowledge to run effectively and reliably, so they are not for everyone! I have had friends sulfate them over one summer because they did not maintain them properly. They have caps for a good reason: to check the battery acid, which tells a much better story about true state of charge than voltage, and makes it possible to equalize a battery in which one cell has become weak, an essential part of maintenance that is usually forgotten by inexperienced users.
No problem starting engines even on coldest days, it behaves just like any other starting battery. At equivalent size, it has about 25% less CCA than the standard automotive starting battery, but considering how technology has evolved over the years it is unlikely that this reduced capacity is actually less than what your vehicle came with in the first place. Just take the largest battery that will fit in your tray and you won't see a difference with a regular starting only battery.
USING AS STANDALONE POWER
Although they are called "Deep Cycle" they are NOT meant to be used in a power generating installation, as they are simply beefed up starting batteries designed to supply some stand alone power. However, compared to a purely starting battery, they won't suffer from actual drain like a starting battery would, as long as you respect recommended discharge rate (don't expect to use 120 amps for one hour in a 120 Amp Hour battery, the rating is for a 20 hour discharge rate, in other words, that large battery is actually designed to run not much more than 75 watt over the duration), use it as little as possible (try to not exceed 50% discharge, or 12.05V at rest) and promptly and properly recharge it after use (although it will give it a usable surface charge, your vehicle's alternator is not designed to do a proper job of it).
KEEP IT CHARGED, USE IT LIGHTLY FOR LONGEVITY
Did I mention it's important not to overly discharge it and with as light a load as possible? It is best to not exceed 50% state of discharge, which means, 60 Ah of use on a 120Ah battery, for a rest voltage of 12.05V. At 11.5V, the battery is totally discharged and MUST be recharged immediately! The more discharged the plates, the greater the risk of irreversible sulfation and the more you deep discharge, the shorter its lifespan will be. In other words, these batteries like to be used little and kept charged up, not like Ni-Cd batteries, more like Li-Ion batteries. Keep in mind the battery warranty is only one year full replacement and another year and a half proportional for a good reason: if you use it exclusively in so-called "deep cycle" mode even with proper maintenance, it won't last more than a couple of years.
COMMON MISTAKES SHORTENING LIFESPAN
- fast discharging with sustained high loads (more than the amp hour rate/10, causing plate material to shed)
- sustained fast charging (more than amp hour rate/10, overheating the plates causing increased corrosion and plate warping)
- deep discharging (consistently to less than 12V before recharging, increasing irreversible sulfation risk)
- not recharging promptly (amorphous, soluble sulfate transforms into crystalline, insoluble sulfate)
- undercharging (relying solely on the vehicle's charging system and voltage, not checking electrolyte density, not equalizing weak cells when needed)
- boiling off (charging without checking and replenishing the cells with distilled water when needed)
- forgetting monthly topping off when not in use
- forgetting most vehicles draw power even when not in use
THE BOTTOM LINE
Versatile battery with sufficient power for use in starting and and running vehicles, with enhanced durability and reserve capacity for light standalone use of the type seen in small recreational craft and family vehicles used for short outings.
Power storage: jack of all trades, master of none. Unsuitable as a battery in an in independent power installation, not designed for regular use as the main source of power such as in an electric vehicle, but great for light use powering accessories for a while with engine off (75W for a day, 300 watts for a few hours), can even be used during the occasional power failure, in conjunction with an inverter, to power some lights and a computer.
Durable and reliable if properly maintained. You have to learn the basics of load capacity, charging, equalizing and general maintenance.
Very good value for the money in terms of versatility, reserve capacity in usefulness if you need it, but poor choice if you want an "Install and forget it" installation and rarely if seldom need to use its reserve capacity ability and are not willing to invest in charging equipment end teach yourself the basics of lead acid battery maintenance.
Properly maintained, this battery can last a long time and give good service for use where you want power for a period of time without having to run your motor or generator. It works well for this use and has enough power to be used for starting a car and with this use in mind is good value for the money.
Is it for everyone? Definitely not, because it requires proper maintenance and will die a quick death if forgotten, and also may not last as long as top of the line, maintenance-free starting batteries when used solely as a staring battery and is definitely not as convenient for that use. But if you are looking for a general purpose battery good for starting your vehicle (car or boat), usable for powering some light accessories when at a stop during an excursion and are willing to learn how to properly take care of it, you'll be pleased with it.
Date published: 2014-04-08
Rated 3 out of
Not a true deep cycle
Almost bought it until I realized it's NOT a deep cycle battery. Product label says it's a deep cycle battery but doing more homework it's not - it's actually a dual purpose (starting and deep cycle) battery. Still good, just misleading and will not deliver to expectations if you were looking for an actual deep cycle battery like I was.
Date published: 2014-03-20